U.S. patent number 5,421,818 [Application Number 08/138,827] was granted by the patent office on 1995-06-06 for multi-functional inner ear treatment and diagnostic system.
This patent grant is currently assigned to Inner Ear Medical Delivery Systems, Inc.. Invention is credited to Irving K. Arenberg.
United States Patent |
5,421,818 |
Arenberg |
June 6, 1995 |
Multi-functional inner ear treatment and diagnostic system
Abstract
A therapeutic treatment apparatus for use in the middle and
inner ear. The apparatus includes a tubular stem portion attached
to a medicine-retaining reservoir with an internal cavity. The
reservoir includes multiple pores therethrough or an opening having
a semipermeable membrane therein which enables medicine delivery
from the reservoir. Such delivery occurs when the reservoir comes
in contact with selected middle-inner ear interface tissues. A
conductive member for receiving electrical potentials from ear
tissues is affixed to the apparatus. Alternatively, the apparatus
may include tubular first and second stem portions secured on
opposite sides of a reservoir along with a conductive member
attached thereto of the type indicated above. This apparatus is
surgically inserted so that the first stem portion is placed within
the inner ear. At least part of the apparatus (the second stem
portion) resides within the external auditory canal. A further
alternative embodiment involves an apparatus with a stem portion, a
reservoir, and an inflatable insert member therein. The insert
member is operatively connected to a temperature-controlled fluid
supply designed to deliver fluids (e.g. gases or liquids) to the
insert causing expansion thereof. Such expansion can
therapeutically modify the pressure characteristics of inner ear
fluids and fluid chambers.
Inventors: |
Arenberg; Irving K. (Englewood,
CO) |
Assignee: |
Inner Ear Medical Delivery Systems,
Inc. (Denver, CO)
|
Family
ID: |
22483844 |
Appl.
No.: |
08/138,827 |
Filed: |
October 18, 1993 |
Current U.S.
Class: |
604/21; 604/20;
604/518 |
Current CPC
Class: |
A61F
11/00 (20130101); A61F 11/006 (20130101); A61M
31/00 (20130101); A61B 90/39 (20160201) |
Current International
Class: |
A61F
11/00 (20060101); A61M 31/00 (20060101); A61B
19/00 (20060101); A61M 025/00 () |
Field of
Search: |
;604/20-21,892.1,96-103,52-53 ;128/DIG.12,24AA |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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|
|
|
|
0223763 |
|
May 1987 |
|
EP |
|
8911882 |
|
Dec 1989 |
|
WO |
|
9211895 |
|
Jul 1992 |
|
WO |
|
Other References
Satoh, Y. et al., "The effect of inline filtration on delivery of
gentamycin at various flow rates", Keio J. Med., vol. 41:(1), pp.
16-20 (Mar. 1992). .
Pillsbury, H. C., III et al. (ed.), Operative Challenges in
Otolaryngology-Head and Neck Surgery, Yearbook Medical Publishers,
Inc., Chicago, 93-101: (1990)-(article therein presented in Chapt.
7 entitled "Nondestructive Surgery for Vertigo-" Approach of I.
Kaufman Arenberg, et al.). .
Pillsbury, H. C., III et al. (ed.), Operative Challenges in
Otolaryngology-Head and Neck Surgery, Yearbook Medical Publishers,
Inc., Chicago, 139-145: (1990)-(article therein presented in Chapt.
10 entitled "Cochlear Implants"-Approach of William M. Luxford et
al.). .
Kingma, G. G. et al., "Chronic drug infusion into the scala tympani
of the guinea pig cochlea", Journal of Neuroscience Methods.
45:127-134 (1992). .
Brookler, K. H. et al., "Closed Loop Water Irrigator System",
Otolaryngol Head Neck Surg., 87:364-365 (May-Jun. 1979). .
Portmann, M., "Eletrophysiological correlates of endolymphatic
hypertension and endolymphatic hydrops: an overview of
electrocochleography (ECoG)", Inner Ear Surgery, 241-247 (1991).
.
Kiil, F., "Molecular mechanisms of osmosis", American Journal of
Physiology, 256-260: (Apr. 1989). .
Erickson, D., "The hole story, fine pore membranes remove viruses
from biological drugs", Scientific American, vol. 267(3), pp.
163-164 (Sep. 1992). .
House, W. F., "Subarachnoid shunt for drainage of hydrops: a report
of 146 cases", Laryngoscope, 75:1547-1551 (1965). .
Densert, B., "Effects of Overpressure on Hearing Function in
Meniere's Disease," Acta Otolaryngol., 103:32-42 (1987)..
|
Primary Examiner: Aschenbrenner; Peter A.
Assistant Examiner: Van Over; Perry E.
Attorney, Agent or Firm: Klaas, Law, O'Meara &
Malkin
Claims
The invention that is claimed is:
1. A treatment apparatus for delivering therapeutic agents into the
inner ear of a human subject comprising:
a reservoir portion comprising a front portion, a rear portion and
a blunt end portion, said blunt end portion comprising a
continuous, uninterrupted exterior surface, said reservoir portion
further comprising an exterior wall and an internal cavity therein
surrounded by said wall;
fluid transfer means within said wall of said reservoir portion for
enabling passage of fluid materials through said wall; and
a tubular stem portion comprising an open first end, a second end,
and a passageway extending continuously through said stem portion,
said second end of said stem portion being connected to said
reservoir portion so that said passageway through said stem portion
is in fluid communication with said internal cavity in said
reservoir portion.
2. The treatment apparatus of claim 1 wherein said fluid transfer
means comprises a section of said wall comprising a plurality of
pores therethrough.
3. The treatment apparatus of claim 1 wherein said wall comprises
an opening therein, and said fluid transfer means comprises a
semi-permeable membrane fixedly secured within said opening.
4. The treatment apparatus of claim 1 wherein said stem portion
further comprises a valve positioned within said passageway
therethrough.
5. The treatment apparatus of claim 1 wherein at least a portion of
said apparatus is radiopaque so that said portion will be visible
during application of X-rays thereto.
6. A treatment apparatus for delivering therapeutic agents into the
inner ear of a human subject comprising:
a reservoir portion comprising an exterior wall and an internal
cavity therein surrounded by said wall, said wall further
comprising an exterior surface;
fluid transfer means within said wall of said reservoir portion for
enabling passage of fluid materials through said wall;
a tubular stem portion comprising an open first end, a second end,
and a passageway extending continuously through said stem portion,
said second end of said stem portion being connected to said
reservoir portion so that said passageway through said stem portion
is in fluid communication with said internal cavity in said
reservoir portion; and
electrical potential transmission means fixedly secured to said
apparatus for transmitting electrical potentials into and out of
said inner ear, said electrical potential transmission means
comprising an elongate conductive member affixed to said exterior
surface of said wall of said reservoir portion.
7. The treatment apparatus of claim 6 wherein said elongate
conductive member further comprises a proximal end and a distal
end, said proximal end being positioned adjacent said reservoir
portion of said apparatus and further comprising a conductive
spherical member fixedly secured thereto.
8. The treatment apparatus of claim 6 wherein said fluid transfer
means comprises a section of said wall comprising a plurality of
pores therethrough.
9. The treatment apparatus of claim 6 wherein said wall comprises
an opening therein, and said fluid transfer means comprises a
semi-permeable membrane fixedly secured within said opening.
10. A method for delivering therapeutic agents through the external
auditory canal of the ear of a human subject and into the middle
ear of said subject so that said therapeutic agents may be
delivered to the round window membrane within said middle ear, said
therapeutic agents thereafter diffusing through said round window
membrane for entry into the inner ear of said subject, said method
comprising the steps of:
providing a treatment apparatus comprising:
a reservoir portion comprising an exterior wall and an internal
cavity therein surrounded by said wall, said internal cavity
comprising a supply of liquid therapeutic agents therein;
fluid transfer means within said wall of said reservoir portion for
enabling passage of fluid materials through said wall; and
a tubular stem portion comprising an open first end, a second end,
and a passageway extending continuously through said stem portion,
said second end of said stem portion being connected to said
reservoir portion so that said passageway through said stem portion
is in fluid communication with said internal cavity in said
reservoir portion;
inserting said reservoir portion of said apparatus into said middle
ear;
placing said first end of said stem portion of said apparatus
within said external auditory canal at a position remotely spaced
from said middle ear; and
positioning said fluid transfer means of said reservoir portion of
said apparatus against and in direct contact with said round window
membrane in said middle ear, said liquid therapeutic agents within
said reservoir portion being delivered from said internal cavity
thereof to said round window membrane by said fluid transfer means
during said direct contact between said fluid transfer means and
said round window membrane, said liquid therapeutic agents
thereafter diffusing through said round window membrane and into
said inner ear.
11. The method of claim 10 further comprising the step of
delivering an additional supply of liquid therapeutic agents
through said external auditory canal and into said first end of
said stem portion of said apparatus while said reservoir portion of
said apparatus is maintained within said middle ear.
12. A method for delivering therapeutic agents through the external
auditory canal of the ear of a human subject and into the middle
ear of said subject so that said therapeutic agents may be
delivered to the round window membrane within said middle ear, said
therapeutic agents diffusing through said round window membrane for
entry into the inner ear of said subject, said method comprising
the steps of:
providing a treatment apparatus comprising:
a reservoir portion comprising an exterior wall and an internal
cavity therein surrounded by said wall, said internal cavity
comprising a supply of liquid therapeutic agents therein;
fluid transfer means within said wall of said reservoir portion for
enabling passage of fluid materials through said wall;
a tubular stem portion comprising an open first end, a second end,
and a passageway extending continuously through said stem portion,
said second end of said stem portion being connected to said
reservoir portion so that said passageway through said stem portion
is in fluid communication with said internal cavity in said
reservoir portion; and
electrical potential transmission means fixedly secured to said
apparatus for transmitting electrical potentials into and out of
said inner ear, said electrical potential transmission means
comprising an elongate conductive member, said conductive member
comprising a proximal end and a distal end;
inserting said reservoir portion of said apparatus and said
proximal end of said conductive member into said middle ear;
placing said first end of said stem portion of said apparatus
within said external auditory canal at a position remotely spaced
from said middle ear;
positioning said fluid transfer means of said reservoir portion of
said apparatus against and in direct contact with said round window
membrane in said middle ear, said liquid therapeutic agents within
said reservoir portion being delivered from said internal cavity
thereof to said round window membrane by said fluid transfer means
during said direct contact between said fluid transfer means and
said round window membrane, said liquid therapeutic agents
thereafter diffusing through said round window membrane and into
said inner ear; and
placing said proximal end of said conductive member in direct
contact with said round window membrane in said middle ear.
13. The method of claim 12 further comprising the step of
delivering an additional supply of liquid therapeutic agents
through said external auditory canal and into said first end of
said stem portion of said apparatus while said reservoir portion of
said apparatus is maintained within said middle ear.
14. A treatment apparatus for delivering therapeutic agents into
the inner ear of a human subject comprising:
a reservoir portion comprising an exterior wall and an internal
cavity therein surrounded by said wall;
fluid transfer means within said wall of said reservoir portion for
enabling passage of fluid materials through said wall;
a tubular stem portion comprising an open first end, a second end,
and a passageway extending continuously through said stem portion,
said second end of said stem portion being connected to said
reservoir portion so that said passageway through said stem portion
is in fluid communication with said internal cavity in said
reservoir portion;
electrical potential transmission means fixedly secured to said
apparatus for receiving electrical potentials from said inner ear;
and
electrocochleographic monitoring means electrically connected to
said electrical potential transmission means for collecting and
characterizing said electrical potentials received from said inner
ear.
Description
BACKGROUND OF THE INVENTION
The present invention generally relates to an apparatus for
therapeutically treating and/or analyzing conditions of the inner
ear, and more particularly to a multi-functional medical apparatus
for use in connection with the inner ear wherein the apparatus is
capable of (1) delivering therapeutic agents to internal ear (e.g.
inner ear) structures; (2) withdrawing fluid materials from the
inner ear; (3) causing temperature, pressure and/or volumetric
changes in the fluids and fluid chambers of the inner ear; and (4)
enabling internal (e.g. inner) ear structures to be
electrophysiologically monitored.
In order to treat various ear disorders, it may often be necessary
to deliver therapeutic agents to inner and middle ear tissues in a
rapid and efficient manner. For example, a variety of structures
have been developed which are capable of delivering/administering
therapeutic agents into the external auditory canal of the outer
ear. U.S. Pat. No. 4,034,759 to Haerr discloses a hollow,
cylindrical tube manufactured of sponge material (e.g. dehydrated
cellulose) which is inserted into the external auditory canal of a
patient. When liquid medicines are placed in contact with the tube,
it correspondingly expands against the walls of the auditory canal.
As a result, accidental removal of the tube is prevented.
Furthermore, the medicine absorbed by the tube is maintained in
contact with the walls of the external auditory canal for treatment
purposes. Other absorbent devices for treatment of the auditory
canal and related tissue structures are disclosed in U.S. Pat. No.
3,528,419 to Joechle, U.S. Pat. No. 4,159,719 to Haerr, and U.S.
Pat. No. 2,642,065 to Negri. The Negri patent specifically
discloses a medicine delivery device with an internally mounted,
frangible medicine container which, when broken, releases liquid
medicines into an absorbent member.
However, the delivery of therapeutic agents in a controlled and
effective manner is considerably more difficult with respect to
tissue structures of the inner ear (e.g. those portions of the ear
contained within the temporal bone which is the most dense bone
tissue in the entire human body). Exemplary inner ear tissue
structures of primary importance include but are not limited to the
cochlea, the endolymphatic sac/duct, the vestibular labyrinth, and
all of the compartments which include these components. Access to
the foregoing inner ear tissue regions is typically achieved
through a variety of structures, including but not limited to the
round window membrane, the oval window/stapes footplate, and the
annular ligament. For the purposes of this invention, these items
in which access to the inner ear,may be accomplished shall be
considered middle-inner ear interface tissue structures as
described in greater detail below. In addition, as indicated
herein, the middle ear shall be defined as the physiological
air-containing tissue zone behind the tympanic membrane (e.g. the
ear drum) and ahead of the inner ear. It should also be noted that
access to the inner ear may be accomplished through the
endolymphatic sac/endolymphatic duct and the otic capsule.
The foregoing inner ear tissues are of minimal size, and only
readily accessible through microsurgical procedures. In order to
treat various diseases and conditions associated with these and
other inner ear tissues, the delivery of medicines thereto is often
of primary importance as previously noted. Exemplary medicines
which are typically used to treat inner ear tissues include but are
not limited to urea, mannitol, sorbitol, glycerol, xylocaine,
epinephrine, immunoglobulins, sodium chloride, steroids, heparin,
hyaluronidase, aminoglycoside antibiotics
(streptomycin/gentamycin), and other drugs, biological materials,
and pharmaceutical compositions suitable for treating tissues of
the human body. Likewise, treatment of inner ear tissues and/or
fluids may involve altering the pressure, volumetric, and
temperature characteristics thereof. Specifically (as will be
described in greater detail below), a precise balance must be
maintained with respect to the pressure of various fluids within
the inner ear and its associated compartments. Imbalances in the
pressure levels of such fluids can cause various problems,
including but not limited to conditions known as endolymphatic
hydrops, endolymphatic hypertension, perilymphatic hypertension,
and perilymphatic hydrops as discussed in greater detail below.
In accordance with the present invention, unique and
specially-designed treatment units are disclosed which are capable
of performing a wide variety of therapeutic functions including but
not limited to (1) the controlled, repeatable, and sustained
delivery of therapeutic agents directly into the inner ear or at
selected middle-inner ear interface tissues; (2) the measurement of
inner ear electrical potentials (evoked or otherwise) using a
technique known as "electrocochleography" (hereinafter "ECoG")
which is described in greater detail below; (3) the alteration of
temperature, volume and pressure conditions within the inner ear;
and (4) the controlled withdrawal of inner ear fluid materials.
Accordingly, the present invention represents an advance in the art
of inner ear treatment and drug delivery as described in detail
below.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a
multi-functional inner ear treatment and diagnostic system which
enables the efficient delivery of therapeutic/diagnostic agents to
selected inner ear tissues and tissue regions.
It is another object of the invention to provide a multi-functional
inner ear treatment and diagnostic system wherein the foregoing
therapeutic/diagnostic agents are delivered either directly into
the inner ear, or through middle-inner ear interface tissues.
It is another object of the invention to provide a multi-functional
inner ear treatment and diagnostic system which enables the
sustained delivery of the foregoing therapeutic/diagnostic agents
to selected inner ear tissues and middle-inner ear interface
tissues in a controlled, repeatable, and uniform manner.
It is yet another object of the invention to provide a
multi-functional inner ear treatment and diagnostic system of
minimal size which is readily inserted within the inner ear or at
middle-inner ear interface tissues using minimally-invasive
microsurgical procedures.
It is a further object of the invention to provide a
multi-functional inner ear treatment and diagnostic system which is
readily supplied with additional quantities of
therapeutic/diagnostic agents while the system is maintained in
position within the ear of a patient.
It is an even further object of the invention to provide a
multi-functional inner ear treatment and diagnostic system having a
subsystem (e.g. an electrode assembly) associated therewith which
is capable of delivering and receiving electrical signals (e.g.
electrical potentials) to and from selected inner ear tissues,
inner ear regions, and middle-inner ear interface tissues for a
wide variety of therapeutic and/or diagnostic purposes.
It is an even further object of the invention to provide a
multi-functional inner ear treatment system having means associated
therewith for changing the temperature, volume and/or pressure
levels of inner ear fluids and fluid chambers.
In accordance with the foregoing objects, the present invention
involves a highly efficient and compact treatment/diagnostic
apparatus for delivering therapeutic agents to inner ear tissues
and tissue regions which interface with the inner ear. The
apparatus is also designed to electrophysiologically measure the
effects of therapeutic agent delivery. The selected therapeutic
agents may either be in liquid form, gel form, or in solid (e.g.
crystalline or powder) forms which are readily hydrated within the
apparatus so that a liquid product is produced on demand. The
apparatus of the present invention is readily inserted in position
through routine microsurgical procedures undertaken by skilled oto
microsurgeons, and likewise preferably includes a conductive
electrode system for receiving resting or evoked electrical
potentials from the inner ear so that they may be analyzed. Such
potentials are typically associated with electrocochleography
("ECoG") procedures as described in greater detail below. The
conductive electrode system described herein may also be used to
deliver electrical waveforms to the inner ear and to selected
middle-inner ear interface tissues.
In a first embodiment of the invention, a multi-functional
treatment/diagnostic apparatus is provided which consists of a body
portion preferably manufactured of a resilient, flexible, and inert
material. It is likewise preferred that the selected construction
material used to produce the body portion be as soft and
stretchable as possible, and entirely devoid of sharp edges. In an
alternative embodiment, the construction material may be selected
so that all or a portion of it is radiopaque (e.g. visible in X-ray
images taken of the body portion). Furthermore, the body portion is
optimally of unitary (e.g. single-piece) construction, although the
invention described herein may likewise be constructed of multiple
components joined together in a conventional manner. The body
portion specifically includes a tubular stem portion having an open
first end, a second end, and a passageway extending continuously
through the stem portion from the first end to the second end
thereof. Operatively and fixedly connected to the second end of the
stem portion is a reservoir portion which, in a preferred
embodiment, is spherical, ovoid, or bulb-like in configuration. The
reservoir portion (which is likewise preferably of single-piece,
unitary construction) is sized to receive and retain a supply of
medicines or diagnostic agents therein, and further includes an
exterior wall and an internal cavity therein surrounded by the
wall. A number of different liquid, gel-type or solid
medicines/diagnostic agents may be received and retained within the
reservoir portion including but not limited to urea, mannitol,
sorbitol, glycerol, xylocaine, epinephrine, immunoglobulins, sodium
chloride, steroids, heparin, hyaluronidase, and aminoglycoside
antibiotics (streptomycin/gentamycin), as well as other drugs,
biological materials, and pharmaceutical compositions suitable for
treating and diagnosing tissues of the human body. In addition, the
reservoir portion may be supplied with medicine precursor materials
(e.g. medicines in solid [crystalline or powder] form) to which
water or other fluids may be added for the in situ production of
liquid medicine materials.
So that the selected medicines may be effectively delivered to
inner ear tissues in a controlled and efficient manner, the
exterior wall of the reservoir portion includes fluid transfer
means therein for enabling the passage of fluid materials (e.g.
liquid medicines) therethrough. In a preferred embodiment, the
fluid transfer means will consist of a section of the wall which is
suitably fenestrated. The term "fenestrated" as used herein shall
involve a section of the foregoing wall which includes a plurality
of pores therethrough which enable fluid flow through the wall on
demand as described in greater detail below. In an alternative
embodiment, the fluid transfer means will involve a portion of the
wall having an opening therethrough. Positioned within the opening
and fixedly secured therein is a semi-permeable membrane system as
described in greater detail below which selectively permits fluid
flow out of the reservoir portion for delivery to inner ear tissues
or selected middle-inner ear tissue regions. Likewise, under
certain circumstances to be described herein, the membrane system
may permit the influx of inner ear fluids into and around the
reservoir portion. These circumstances specifically involve
situations in which chemical agents (e.g. mannitol crystals) are
used which cause an osmotic pressure gradient within the reservoir
portion that is sufficient to draw inner ear fluid materials into
or around the reservoir portion in accordance with standard
dialysis/diuresis concepts.
In a preferred embodiment, the medicine delivery apparatus
described herein further includes electrical potential transmission
means (e.g. an active electrode system) fixedly secured to the body
portion for receiving resting or evoked electrical potentials from
the inner ear (or middle-inner ear interface tissues) and
transmitting the electrical potentials therefrom. These potentials
are then analyzed in accordance with a specialized process known as
electrocochleography or "ECoG" (described in greater detail below).
The electrical potential transmission means preferably consists of
at least one elongate conductive member affixed to the outer
surface of the body portion. In a preferred embodiment, the
elongate conductive member comprises a conductive wire having a
proximal end, a medial section, and a distal end, with the proximal
end being positioned directly adjacent the fluid transfer means of
the reservoir portion. As a result, the proximal end is able to
come in direct contact with the tissues (e.g. middle-inner ear
interface tissues) to which medicine is being delivered using the
apparatus of the present invention. Optimally, the proximal end of
the wire includes a conductive spherical member or club/hook-like
portion fixedly secured thereto (e.g. formed as an integral part
thereof). The distal end of the wire is operatively connected to an
external monitoring apparatus designed to analyze and interpret
electrical potentials received from the foregoing ear tissues which
may be generated in response to clicks, tone-bursts, pips or other
sounds produced in accordance with standard ECoG procedures.
In order to use the multi-functional treatment apparatus of the
present invention, the apparatus is surgically inserted and
positioned within the middle ear of a patient so that the fluid
transfer means of the reservoir portion is in direct physical
contact with a selected middle-inner ear interface tissue
structure. Surgical insertion and placement in this manner is
normally accomplished via an incision in the tympanic membrane
which is undertaken using standard tympanotomy procedures.
Alternatively, insertion and placement of the apparatus may be
accomplished using a standard tympanomeatal flap incision which
likewise provides access to the middle ear and structures thereof.
An exemplary and preferred middle-inner ear interface tissue
structure suitable for the purposes set forth herein is the round
window membrane, which is a thin, membranous structure through
which liquids may diffuse in multiple directions. In addition, the
apparatus of the present invention is preferably oriented so that
at least a section of the stem portion (e.g. the open first end)
extends through the incised tympanic membrane (or under the
foregoing tympanomeatal flap), and resides within the external
auditory canal of the patient.
The apparatus described herein is either pre-filled with a selected
liquid medicine prior to insertion, or may be filled after
insertion using a conventional syringe/needle assembly wherein the
needle is inserted into the external auditory canal of the patient,
and into the open first end of the stem portion of the medicine
delivery apparatus. The liquid medicine is then delivered from the
syringe into the stem portion, thereby filling the reservoir
portion. Alternatively, the reservoir portion of the apparatus may
be pre-filled with solid (e.g. crystalline, gel or powder) medicine
precursor materials which are thereafter combined with water or
other fluids (using the above-described conventional syringe
assembly) to produce a supply of liquid medicine on demand within
the reservoir. In addition, other systems instead of the foregoing
syringe unit may be used to deliver liquid materials to the
reservoir portion of the medicine delivery apparatus including but
not limited to system known as an osmotic pump which is described
in Kingma, G. G., et al., "Chronic drug infusion into the scala
tympani of the guinea pig cochlea", Journal of Neuroscience
Methods, 45:127-134 (1992). An exemplary, commercially-available
osmotic pump may be obtained from the Alza Corp. of Palo Alto,
Calif. (USA).
Immediately upon contact between the fluid transfer means of the
reservoir portion and the selected middle-inner ear interface
tissue structure (e.g. the round window membrane), liquid medicines
retained within the reservoir portion are drawn osmotically or by
capillary action through the exterior wall via the fluid transfer
means. This situation continues until most or all of the liquid
medicines are withdrawn from the reservoir portion. At that point
(or after the passage of a selected time interval), the medicine
delivery apparatus is either withdrawn from the patient or refilled
with medicine, with the entire process thereafter being repeated.
With respect to liquid medicines, refilling may be accomplished
through the external auditory canal using a syringe (or other
comparable system) in the same manner described above regarding the
initial delivery of liquid medicines into the medicine delivery
apparatus. Also, if undissolved solid (e.g. crystalline, gel, or
powder) medicine precursor materials remain within the reservoir
portion, further quantities of water or other liquid materials may
be added thereto using the foregoing syringe or other system in
order to create additional quantities of liquid medicine in situ.
It should likewise be noted that the stem portion may include an
optional one-way fluid control valve therein (as described in
greater detail below) in order to prevent and/or control the flow
of liquid medicines outwardly in a reverse direction from the
reservoir portion through the stem portion.
In addition, as will be described herein, various chemical
compositions may be placed within the reservoir portion which
create an osmotic pressure gradient sufficient to draw liquid
materials (e.g. inner ear fluids) out of the inner ear through the
above-described middle-inner ear interface tissues. For example,
this type of situation would result when a semi-permeable membrane
is used in connection with a reservoir portion having a supply of
mannitol crystals therein. Hydration of such crystals through the
introduction of water (or saline solution) in the manner set forth
above will create a high concentration of mannitol at the selected
middle-inner ear interface tissues. As a result, an osmotic
pressure gradient is produced as described above, thereby drawing
inner ear fluids out of the inner ear through the selected
middle-inner ear interface tissues (e.g. the round window
membrane). The withdrawn inner ear fluids will then be drawn into
the reservoir portion of the apparatus through the semi-permeable
membrane, or will be deposited outside of the reservoir portion in
various regions adjacent thereto.
To measure resting or evoked electrical potentials from selected
inner ear tissues in accordance with standard ECoG procedures
(described in greater detail below), the apparatus of the present
invention is manipulated so that the proximal end of the conductive
wire (e.g. having the spherical member or hook-like member thereon)
is placed in direct contact with the middle-inner ear interface
tissues of concern (e.g. the round window membrane or stapes
footplate). Electrical potentials from the inner ear which are
received by the foregoing interface tissue structures are then
transmitted along the wire to the distal end thereof. In a
preferred embodiment, the wire is sufficiently long to permit the
distal end thereof to extend through the incised tympanic membrane
(or tympanomeatal flap) and the external auditory canal so that the
distal end terminates at a position outside of the patient's ear.
The distal end of the wire is thereafter connected using standard
electrical coupling components to an external monitoring apparatus
designed to collect and characterize various inner ear electrical
potentials in accordance with known ECoG procedures. In this
manner, the apparatus of the present invention enables the
controlled, effective delivery of medicine materials to selected
ear tissues, and simultaneously enables inner ear electrical
potentials to be efficiently measured, monitored, and analyzed.
Monitoring of the foregoing electrical potentials will allow the
treating physician to interpret and analyze the
function/dysfunction of the inner ear in response to various
changes in inner ear conditions caused by the addition of
medicines, as well as induced changes in the temperature, volume,
and/or pressure of fluid and tissue materials within the inner
ear.
In an alternative embodiment of the invention, the treatment
apparatus of the present invention again includes a body portion
preferably of unitary (e.g. single-piece) construction which is
manufactured from a resilient, elastic, and inert material of the
same type set forth above. Again, this material should be as soft
and stretchable as possible, with all or part of the body portion
being radiopaque. The body portion includes a tubular first stem
portion having an open first end, a second end, and a passageway
extending continuously through the first stem portion from the open
first end to the second end. Operatively and fixedly connected to
the second end of the first stem portion is a reservoir portion
which, in a preferred embodiment, is again spherical, ovoid, or
bulb-like in configuration. The reservoir portion is sized to
receive and retain a supply of medicines or diagnostic agents
therein (e.g. in liquid, gel, or solid [crystalline or powder] form
as noted above), and further includes an exterior wall and an
internal cavity therein surrounded by the wall. Once again, a
number of different medicine materials/diagnostic agents may be
received and retained within the reservoir portion including but
not limited to the compositions listed above.
The body portion of the medicine delivery apparatus further
includes a tubular second stem portion substantially identical in
construction and configuration to the first stem portion, although
it is preferred that the second stem portion be slightly longer
than the first stem portion. The second stem portion includes an
open first end, a second end, and a passageway extending
continuously through the second stem portion from the open first
end to the second end. The second end of the second stem portion is
operatively and fixedly connected to the reservoir portion. In a
preferred embodiment, the first stem portion is positioned on a
first side of the reservoir portion, while the second stem portion
is positioned on a second side of the reservoir portion. Optimally,
the first side of the reservoir portion is directly opposite the
second side of the reservoir portion so that, in a preferred
embodiment, the first and second stem portions are on opposite
sides of the reservoir portion and in axial alignment with each
other. In addition, at least one of the first and second stem
portions may optionally include at least one fluid flow control
valve of conventional construction therein at one of several
pre-selected locations so that the directional flow of fluids
therethrough may be precisely controlled.
The foregoing alternative embodiment of the medicine delivery
apparatus likewise preferably includes electrical potential
transmission means fixedly secured to the exterior surface of the
body portion for receiving resting or evoked electrical potentials
from selected inner ear tissues. These potentials are then
transmitted out of the inner ear for the detection and analysis
thereof in accordance with standard ECoG procedures as indicated
above. In a preferred embodiment, the electrical potential
transmission means again involves an elongate conductive member
affixed to the exterior surface of the body portion. The conductive
member preferably consists of an elongate conductive wire which
includes a proximal end, a medial section, and a distal end, with
the proximal end being positioned adjacent the second end of the
first stem portion (e.g. at the juncture between the first stem
portion and the reservoir portion). Alternatively, the proximal end
of the conductive wire may be positioned adjacent the open first
end of the first stem portion. As a result, the proximal end is
able to come in direct contact with the ear tissues of concern as
described below. Optimally, the proximal end of the wire includes a
conductive spherical member or club/hook-like member fixedly
secured thereto (e.g. integrally formed thereon) as indicated
above. The distal end of the wire is operatively connected to an
external monitoring apparatus designed to analyze and interpret
electrical potentials (e.g. ECoG potentials) received from inner
ear tissues and/or middle-inner ear interface tissues.
In order to use the foregoing alternative embodiment of the
apparatus described above, it is surgically inserted within the
middle ear (e.g. so that the reservoir portion is entirely
positioned within the middle ear). Surgical insertion in this
manner is preferably accomplished through an incision in the
tympanic membrane using conventional surgical tympanotomy
procedures or alternatively through the use of a tympanomeatal flap
procedure as described above. Thereafter, using standard
microsurgical techniques, the first stem portion is inserted
through a previously-selected middle-inner ear interface tissue
structure. In a preferred embodiment, the first stem portion is
positioned through a discrete opening formed through the stapes
footplate (and underlying oval window) or through the
cochlear/vestibular otic capsule bone. This opening (formed using
laser energy or microdrill techniques) provides access from the
middle ear and/or mastoid space into any or all of the various
inner ear compartments for the direct placement of the first stem
portion therein. As a result, the open first end of the first stem
portion is positioned adjacent to and in direct contact with the
inner ear fluids (e.g. endolymph and/or perilymph), tissues,
compartments, and/or tissue regions to be treated. It should also
be noted that the body portion of the foregoing alternative
medicine delivery apparatus is suitably positioned so that at least
a section of the second stem portion (e.g. the open first end
thereof) passes through the incised tympanic membrane (or beneath
the foregoing tympanomeatal flap), and resides within the external
auditory canal of the ear.
As stated above relative to the first embodiment of the medicine
delivery apparatus, the foregoing alternative apparatus is either
pre-filled with a selected liquid, gel, or solid medicine (e.g.
crystals or powder) prior to insertion, or may be filled with
liquid medicine after insertion using a conventional syringe/needle
apparatus wherein the needle is inserted into the external auditory
canal of the patient, and thereafter into the open first end of the
second stem portion. The liquid medicine is then delivered from the
syringe into the second stem portion, thereby filling the reservoir
portion and (in a preferred embodiment), most or all of the first
stem portion. An osmotic pump system as previously described may
also be used instead of the foregoing syringe.
Alternatively, as noted above, the reservoir portion of the
apparatus may be pre-filled with gel or solid (e.g. crystalline or
powder) medicine materials which are thereafter combined with water
or other solvating fluids (using the above-described conventional
syringe assembly) to produce a supply of liquid medicine in situ
within the reservoir portion on demand.
In order to effectively use the foregoing alternative embodiment of
the medicine delivery apparatus, the open first end of the first
stem portion is positioned against and/or in direct contact with
the inner ear fluids, fluid compartments, tissues or tissue regions
to be treated. Immediately upon such contact, liquid medicines
within the first stem portion and the reservoir portion are drawn
outwardly therefrom by capillary action or osmotic forces so that
they are effectively applied/delivered to the tissues,
compartments, or tissue regions of concern. This action continues
until most or all of the medicine is withdrawn from the reservoir
portion. At that point (or after the passage of a selected time
interval), the medicine delivery apparatus is either refilled with
liquid medicine or withdrawn from the patient (surgically or by
extraction through the incised tympanic membrane and external
auditory canal). As noted above, refilling of the medicine delivery
apparatus with liquid medicines may be accomplished through the
external auditory canal using a needle assembly (or other
comparable system) in the same manner previously described
regarding the initial delivery of liquid medicines into the
medicine delivery apparatus. Also, if undissolved gel or solid
(e.g. crystalline or powder) medicine precursor materials remain
within the reservoir portion, further quantities of water or other
hydrating liquids may be added thereto using the foregoing syringe
or other system in order to create additional quantities of liquid
medicine in situ for the continued delivery thereof.
To measure resting or evoked electrical potentials from selected
inner ear tissues in accordance with standard ECoG procedures (set
forth below), the present alternative embodiment of the invention
is manipulated (if necessary) so that the proximal end of the
conductive member (e.g. the proximal end of the wire having the
foregoing spherical member or hook-like member thereon)I is
positioned against and in direct contact with the selected tissue
structures of concern (e.g. the stapes footplate). Electrical
potentials which pass through such tissue structures from the inner
ear are then transmitted along the wire to the distal end thereof.
In a preferred embodiment, the wire is sufficiently long to permit
the distal end thereof to extend through the incised tympanic
membrane (or beneath the tympanomeatal flap) and through the
external auditory canal so that the distal end again terminates at
a position outside of the patient's ear. The distal end of the wire
is thereafter connected to an external monitoring apparatus
designed to collect and characterize inner ear electrical
potentials in accordance with known ECoG procedures.
In a still further alternative embodiment of the present invention,
means are provided wherein changes in inner ear fluid pressure,
temperature, and/or volume levels may be accomplished. As
previously indicated, a precise balance exists with respect to the
fluids of the inner ear (e.g. the endolymph and the perilymph).
These fluids reside within discrete tissue structures, with the
endolymph being retained in the membranous endolymphatic system and
the perilymph being held in the membranous perilymphatic system.
Such fluids are maintained within a precise balance relative to
each other. If this balance does not exist, numerous problems may
result. For example, if the endolymphatic fluid pressure exceeds
the perilymphatic fluid pressure in the inner ear for any reason,
conditions known as endolymphatic hypertension and endolymphatic
hydrops can result. In a patient, endolymphatic hydrops is
manifested on a clinical basis by some or all of the following
conditions: episodic vertigo, sensations of fullness/pressure in
the ear, fluctuating sensory hearing, and ear noise (e.g.
tinnitus). Endolymphatic hydrops is the underlying physiological
cause of a clinical condition known as "Meniere's Disease". In
contrast, if the perilymphatic fluid pressure within the inner ear
exceeds the endolymphatic fluid pressure, perilymphatic
hypertension will result.
Tests and studies have shown that the application of pressure to
the inner ear from selected regions within the middle ear will
result in temporary or permanent changes in the pressure balance of
endolymph and perilymph relative to each other. These changes have
been measured electrophysiologically using standard ECoG techniques
as described above. In the present invention, means are provided
wherein pressure changes relative to the foregoing fluids may be
accomplished in a minimally invasive manner. As described below,
these changes are undertaken by the direct application of physical
pressure to selected tissue structures, with such physical pressure
being transmitted directly to the foregoing fluids. Alternatively,
changes in fluid pressure may be accomplished by increasing or
decreasing the temperature of such fluids which causes
corresponding changes in fluid volume and pressure levels. For
example, an increase in fluid temperature will result in a thermal
expansion of the fluid, thereby increasing its volume and pressure
in accordance with known physical relationships involving the
pressure, temperature, and volume of fluid materials.
To specifically achieve the foregoing changes in inner ear fluid
temperature, pressure, and volume levels, a modified
multi-component treatment system is provided. Specifically, this
system first includes a primary treatment apparatus of
substantially the same type described above with respect to the
first embodiment of the present invention. The primary treatment
apparatus comprises a body portion having a reservoir portion and
an elongate stem portion extending outwardly therefrom. The stem
portion includes an open first end and a second end attached to the
reservoir portion. The reservoir portion has the same
characteristics set forth above (including an internal cavity
therein), and further preferably includes fluid transfer means of
the same type previously described (e.g. a plurality of pores or a
semi-permeable membrane). However, in the present embodiment, the
fluid transfer means may be omitted from the reservoir portion if
desired. The primary treatment apparatus of the present embodiment
may likewise include electrical potential transmission means (e.g.
a conductive wire member) of the same type set forth above in the
first embodiment of the invention.
The distinguishing characteristic of this embodiment of the
invention involves the use of an inflatable insert member which is
positioned within the body portion of the primary treatment
apparatus. The insert member includes a spherical, ovoid, or
bulb-like fluid receiving portion with an exterior wall and an
internal chamber surrounded by the wall. However, it is important
to note that the fluid receiving portion does not include fluid
transfer means therein (e.g. pores, membranes, or the like). The
insert member is designed for receipt within the body portion of
the primary treatment apparatus as noted above. The fluid receiving
portion (in a deflated condition) is smaller in size than the
reservoir portion of the primary treatment apparatus, and therefore
will not block the fluid transfer means in the primary treatment
apparatus when the delivery of medicine therefrom is desired.
However, it is preferred that the fluid receiving portion of the
insert member be configured in substantially the same shape as the
internal cavity of the reservoir portion in the primary treatment
apparatus so that the fluid receiving portion will conform
therewith when inflated with gases or liquids.
The fluid receiving portion and remaining components of the insert
member are preferably manufactured of a resilient, flexible, and
inert material. Once again, it is likewise preferred that the
selected construction material used to produce the insert member be
as soft, elastic, and stretchable as possible, and entirely devoid
of sharp edges. The construction material may be selected so that
all or a portion of it is radiopaque. Furthermore, the insert
member is preferably of single-piece, unitary construction.
However, it is preferred that the walls of the insert member be
thinner than the corresponding walls of the primary treatment
apparatus.
The fluid receiving portion of the insert member is fixedly
connected to an elongate tubular portion which is sufficiently long
so that it terminates within the external auditory canal or
entirely outside of the ear. In a preferred embodiment, the tubular
portion has a diameter which, in a deflated state, is sufficiently
small to enable it to fit within the stem portion of the primary
treatment apparatus. Likewise, the tubular portion of the insert
member is preferably longer than the stem portion of the primary
treatment apparatus. The tubular portion further includes an open
first end (the function of which will be described hereinafter), a
second end fixedly connected to the bulb-like fluid receiving
portion, and a passageway extending continuously from the first end
to the second end.
The primary treatment apparatus with the insert member therein is
then surgically inserted and positioned within the middle ear of a
patient so that the reservoir portion of the primary treatment
apparatus is in direct physical contact with a selected
middle-inner ear interface tissue structure. Surgical insertion and
placement in this manner is normally accomplished via an incision
in the tympanic membrane which is undertaken using standard
tympanotomy procedures. Alternatively, insertion and placement of
the apparatus may be accomplished using a standard tympanomeatal
flap incision which likewise provides access to the middle ear and
structures thereof. An exemplary and preferred middle/inner ear
tissue structure suitable for the purposes set forth herein is the
round window membrane. In addition, the primary treatment apparatus
is preferably oriented so that at least a section of the stem
portion (e.g. the open first end thereof) extends through the
incised tympanic membrane (or beneath the foregoing tympanomeatal
flap), and resides within the external auditory canal of the
patient.
The open first end of the tubular portion associated with the
insert member is then operatively connected to either an external
supply of fluid (e.g. air, water, or other liquids/gases) via a
conduit passing through the external auditory canal. The conduit
includes a first end operatively connected to the external supply
of fluid and a second end operatively connected to the open first
end of the tubular portion. In order to selectively change or
stabilize the temperature, pressure, and volume of inner ear fluid
materials/fluid chambers, a fluid material from the external supply
thereof is delivered to the insert member. Specifically, a selected
gas or liquid is delivered through the foregoing conduit, through
the tubular portion of the insert member, and into the fluid
receiving portion thereof. The selected fluid is supplied at a
pressure sufficient to cause volumetric expansion of the fluid
receiving portion which is able to occur due to the stretchable
materials used to produce it. As this occurs, the fluid receiving
portion of the insert member fills the internal cavity of the
reservoir portion in the primary treatment apparatus, and
thereafter causes the reservoir portion to expand. Since the
reservoir portion is positioned against a selected middle-inner ear
interface tissue structure (e.g. the round window membrane),
pressure is exerted against the selected structure which is
transmitted to the fluid and tissue materials within the inner ear.
Also, the supply of fluid materials for use in connection with this
embodiment may likewise include a temperature control system for
heating or cooling the selected fluid materials being delivered.
The delivery of a heated gas or liquid to the fluid receiving
portion of the insert member will cause a corresponding increase in
the temperature of the reservoir portion of the primary treatment
apparatus. This increase in temperature is then conductively
transmitted from the reservoir portion into the inner ear via the
selected middle-inner ear interface tissue structure. The heated
inner ear fluids will thereafter expand, causing the volume and
pressure characteristics of the fluids to increase. The opposite
result will be achieved if cooled gases or liquids are delivered to
the fluid receiving portion of the insert member. It should
likewise be noted that the delivery of fluids to the insert member
may be undertaken in discrete pulses if desired, or in a single,
sustained infusion. Also, in addition to causing the foregoing
effects on inner ear fluids/compartments, expansion of the insert
member may likewise be used to physically force medicine materials
from the reservoir portion of the primary treatment apparatus
through the fluid transfer means (if used).
The foregoing embodiments of the multi-functional treatment
apparatus of the present invention represent an advance in the art
of the inner ear treatment, diagnosis, monitoring, and therapy.
They enable the controlled, rapid, and effective delivery of
medicines to selected middle or inner ear tissues/fluid
compartments, and simultaneously enable inner ear electrical
potentials to be efficiently measured and analyzed. As a result,
the effects of medicine delivery on inner ear tissues may be
monitored. Likewise, the temperature, pressure, and volumetric
characteristics of inner ear fluids/fluid chambers may be favorably
modified using the apparatus of the present invention. These
benefits are accomplished with a minimal amount of microsurgery,
and are achieved with a maximum degree of simplicity and
effectiveness. These and other objects, features, and advantages of
the invention will be described below in the following Brief
Description of the Drawings and Detailed Description of Preferred
Embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an enlarged front perspective view of a primary
embodiment of a multi-functional treatment apparatus produced in
accordance with the present invention for use in the human ear.
FIG. 2 is an enlarged side view of the treatment apparatus of FIG.
1 having part of the stem portion thereof broken away to show the
interior thereof.
FIG. 3 is an enlarged side view of the proximal end of an
alternative embodiment of the conductive wire used in connection
with the treatment apparatus of FIG. 1 to receive/transmit
electrical signals.
FIG. 4 is an enlarged front view of the treatment apparatus of FIG.
1 which illustrates one embodiment of the fluid transfer means
associated with the reservoir portion of the apparatus.
FIG. 5 is an enlarged front view of the treatment apparatus of FIG.
1 which illustrates an alternative embodiment of the fluid transfer
means associated with the reservoir portion of the apparatus.
FIG. 6 is an enlarged front perspective view of a multi-functional
treatment apparatus for use in the human ear produced in accordance
with an alternative embodiment of the present invention.
FIG. 7 is an enlarged side view of the alternative treatment
apparatus of FIG. 6.
FIG. 8 is an enlarged end view of the alternative treatment
apparatus of FIG. 6 showing the first stem portion thereof.
FIG. 9 is a schematic, partial cross-sectional view of the ear of a
human subject illustrating the treatment apparatus of FIG. 1
inserted therein.
FIG. 10 is an enlarged side view of the proximal end of an
alternative embodiment of the conductive wire used in connection
with the treatment apparatus of FIG. 6 to receive/transmit
electrical signals.
FIG. 11 is a schematic, partial cross-sectional view of the ear of
a human subject illustrating the treatment apparatus of FIG. 6
inserted therein.
FIG. 12 is an enlarged front perspective view of a further
alternative multi-functional treatment apparatus wherein the
apparatus of FIG. 6 has been modified to include additional
structural components.
FIG. 13 is an enlarged, exploded side view of a specialized
multi-component treatment system designed to induce temperature,
volume, and pressure changes with respect to the fluids of the
human ear and deliver medicine materials to internal ear
tissues.
FIG. 14 is an enlarged, assembled, cross-sectional side view of the
multi-component treatment system of FIG. 13.
FIG. 15 is a schematic, partial cross-sectional view of the ear of
a human subject illustrating the multi-component treatment system
of FIG. 14 inserted therein.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The present invention involves a highly efficient multi-functional
treatment apparatus specifically designed for use in treating
and/or diagnosing the inner ear of a human subject. Specifically,
the invention as described herein has numerous functional
capabilities including but not limited to (1) delivering
therapeutic agents into the inner ear or to middle-inner ear
interface tissues; (2) withdrawing fluid materials from the inner
ear; (3) causing temperature, pressure and volumetric changes in
the fluids/fluid chambers of the inner ear; and (4) enabling inner
ear structures to be electrophysiologically monitored.
With particular reference to FIGS. 1-5, a primary embodiment of a
multi-functional treatment apparatus 10 produced in accordance with
the present invention is schematically illustrated. The apparatus
10 includes a body portion 12 which, as noted above, is preferably
of unitary (e.g. single-piece), molded construction. In a preferred
embodiment, the body portion 12 is manufactured of a soft,
resilient, stretchable (elastic), and biologically inert material.
The flexibility and softness of the body portion 12 is of
particular importance in order to avoid damage to delicate middle
and inner ear tissues during the insertion or removal thereof, and
is likewise important for other reasons as described below.
Exemplary construction materials suitable for this purpose include
but are not limited to medical grade silicone rubber, medical grade
teflon, and a commercially-available, biodegradable
gelatin-cellulose composition sold under the name Gelfilm.TM. which
may be obtained from the Upjohn Company of Kalamazoo, Mich.
(USA).
In addition, in certain instances, it may be desirable to
manufacture all of part of the body portion 12 from medical grade
silicone rubber impregnated with BaSO.sub.4 or any other suitable
materials (e.g. heavy metal compositions) having similar
characteristics which will render all or part of the body portion
12 radiopaque when X-rays are applied thereto. Specifically, the
term "radiopaque" signifies a condition wherein the body portion 12
will be visible in X-ray images taken of a patient having the
treatment apparatus 10 inserted therein. This will enable the
treating physician to accurately determine the precise location of
the apparatus 10 within a patient after insertion.
With continued reference to FIGS. 1-2, the body portion 12 further
includes a tubular stem portion 14. The term "tubular" as used
herein shall generally signify an elongate structure having a bore
or passageway therethrough surrounded by a continuous wall. As
shown in FIG. 2, the stem portion 14 includes a continuous side
wall 16 which is preferably annular (e.g. circular or ring-like) in
cross-section. The stem portion 14 further includes an open first
end 20, a second end 22, and a passageway 24 extending continuously
through the stem portion 14 from the open first end 20 to the
second end 22. In a preferred embodiment for use in connection with
the human ear, the stem portion 14 will have a diameter "D.sub.1 "
which is uniform along the entire length thereof from the open
first end 20 to the second end 22. Optimally, for use in connection
with the human ear, the diameter "D.sub.1 " will be about 0.2-2.0
mm. It should be noted that this diameter range (as well as other
quantitative specifications and construction materials set forth
herein) is for example purposes only, and the present invention
shall not be limited to any particular sizes, dimensions, or
physical parameters. Furthermore, the length "L.sub.1 " (FIG. 1) of
the stem portion 14 will preferably be about 8.5-23.0 mm.
With continued reference to FIGS. 1-2, the second end 22 of the
stem portion 14 is operatively and fixedly connected to an enlarged
reservoir portion 30 which is designed to retain a supply of
liquid, gel-type, or solid (e.g. crystalline or powdered) medicines
therein. As indicated above, it is preferred the body portion 12 of
the treatment apparatus 10 be of unitary (e.g. single-piece) molded
construction. In this regard, the stem portion 14 and the reservoir
portion 30 are, in a preferred embodiment, integrally formed
together during production of the apparatus 10. Either the stem
portion 14, the reservoir portion 30, or both of these components
may be made radiopaque during the foregoing production process as
noted above.
The reservoir portion 30 may involve numerous different external
configurations. With reference to FIGS. 1-2, the reservoir portion
30 is configured in an oval (e.g. ovoid) shape with a front portion
32, a rear portion 33, and a substantially blunt end portion 34.
However, the reservoir portion 30 may also resemble a sphere, bulb,
or other comparable configuration. In this regard, the reservoir
portion 30 of the present invention shall not be limited to any
particular external shape. As illustrated in FIG. 2, the reservoir
portion 30 further includes an internal cavity 38 which is adapted
to receive liquid, gel-type, or solid medicines therein. An
exemplary supply of liquid medicine within the internal cavity 38
is illustrated in FIG. 2 at reference number 39. Attachment of the
second end 22 of the stem portion 14 to the reservoir portion 30 in
the foregoing manner enables the passageway 24 in the stem portion
14 to be in fluid communication with the internal cavity 38 as
illustrated in FIG. 2. While the volumetric capacity of the
internal cavity 38 may be suitably varied during manufacture of the
apparatus 10, it is preferred that the internal cavity 38 have a
capacity of about 3.0-6.0 ml. Furthermore, as illustrated in FIG.
1, it is preferred that the reservoir portion 30 have a length
"L.sub.2 " of about 3.0-8.8 mm, and a thickness "T.sub.1 " of about
2.0-8.8 mm with respect to embodiments of the apparatus 10 which
are designed for use in the human ear. The overall length "L.sub.3
" of the body portion 12 will preferably be about 11.5-31.8 mm
which will readily enable placement of the treatment apparatus 10
into the middle ear of the patient so that the apparatus 10 can
contact the selected middle-inner ear interface tissues as
described below.
As illustrated in FIG. 2, the internal cavity 38 of the reservoir
portion 30 is surrounded by an exterior wall 42. So that medicine
materials retained within the internal cavity 38 of the reservoir
portion 30 may be effectively delivered to desired tissues within
the middle and/or inner ear, the wall 42 includes fluid transfer
means therein generally designated at reference number 43 in FIGS.
1, 2, and 4. As illustrated in FIGS. 1, 2, and 4, the fluid
transfer means 43 consists of a fenestrated zone 44 which is
positioned within the front portion 32 of the reservoir portion 30.
The term "fenestrated" as used herein involves a portion of the
wall 42 having a plurality of pores 46 (enlarged for the sake of
clarity in FIGS. 1, 2 and 4) therethrough. The pores 46 enable
liquid medicines to pass out of the internal cavity 38 of the
reservoir portion 30 during use of the treatment apparatus 10.
Also, in certain instances to be described below, the pores 46 will
enable fluid materials (e.g. inner ear fluids) to be drawn into the
reservoir portion 30. The size and quantity of the pores 46 may be
varied during production of the apparatus 10. However, by way of
example, the apparatus 10 will optimally include about 30-40 pores
46, with each pore 46 having a diameter of about 0.005-0.245 mm.
The pores 46 may all be of a uniform diameter (e.g. the same size),
or may involve numerous pores 46 of mixed diameters (e.g. different
sizes), preferably all of which are within the foregoing diameter
range. The pores 46 are specifically sized to control/minimize the
spontaneous leakage of fluids (e.g. liquid medicines) outwardly
from the internal cavity 38 of the reservoir portion 30. Instead,
the liquid medicines will be delivered by capillary/osmotic action
from the internal cavity 38 of the reservoir portion 30 when the
fenestrated zone 44 of the wall 42 is placed in direct physical
contact with the tissues of concern as described in greater detail
below. In contrast, if solid (e.g. crystalline or powdered) or
gel-type medicine precursor materials are used within the reservoir
portion 30 (as described in greater detail below), such materials
will not pass through the pores 46 in the reservoir portion 30
until suitably activated (e.g. solvated/hydrated) using water or
other selected aqueous activator materials (saline solution and the
like). As a result of such activation, and through the exertion of
osmotic and capillary forces, the resulting liquid medicine
materials produced in situ will then pass through the pores 46 upon
contact with the selected ear tissues.
An alternative embodiment of the foregoing fluid transfer means 43
is schematically illustrated in FIG. 5. Specifically, in the
embodiment of FIG. 5, the wall 42 of the reservoir portion 30
includes an opening 50 through the front portion 32. The size of
the opening 50 may again be varied during production of the
treatment apparatus 10, but is preferably elliptical in
configuration with a length "L.sub.4 " of about 10-4.0 mm and a
width "W.sub.1 " of about 10-6.0 mm (FIG. 5). Fixedly positioned
within the opening 50 and secured to the peripheral edges 51
thereof is a semipermeable membrane 54 of a type known in the art
which permits fluid to selectively flow outwardly therefrom, but
will not encourage resident tissue fluids and the like to flow
inwardly into the internal cavity 38 of the reservoir portion 30
unless certain circumstances are present as described below.
Exemplary semi-permeable membranes suitable for use in the present
invention include but are not limited to those which are known in
the art and described in Kiil, F., "Molecular mechanisms of
osmosis", Am J. Physiology, 256-260:(April 1989); Erickson, D.,
"The hole story, fine pore membranes remove viruses from biological
drugs", Sci. American, vol. 267(3), pp. 163-164 Satoh, Y. et al.,
"The effect of inline filtration on delivery of gentamycin at
various flow rates", Keio J. Med., vol. 41:(1), pp. 16-22 (March
1992) which are incorporated herein by reference. Alternatively,
although the use of a membrane 54 is preferred, the membrane 54 may
be substituted with a micropore filter known in the art (not shown)
and suitable for the purposes set forth herein. An exemplary filter
for this purpose would consist of a product sold by PALL Ultrafine
Filtration Co. of East Hills, N.Y. (USA) (type PALL 0.2 microns).
Comparable filters are also available from Millipore, Inc. of
Bedford, Mass. (USA).
Referring back to FIG. 5, the peripheral edges 57 of the membrane
54 are fixedly secured to the peripheral edges 51 of the opening 50
preferably using a conventional adhesive. Exemplary adhesives
suitable for this purpose would include but not be limited to a
conventional cyanoacrylate adhesive or other adhesive composition
known in the art. When the membrane 54 is placed in direct physical
contact with the ear tissues of concern (e.g. the selected
middle-inner ear interface tissues), liquid medicines retained
within the internal cavity 38 of the reservoir portion 30 will be
drawn outwardly therefrom through the membrane 54 by capillary
action and/or osmotic forces. The inward flow of resident tissue
fluids and the like into the internal cavity 38 of the reservoir
portion 30 is effectively prevented by the semi-permeable character
of the membrane 54 except under special circumstances as set forth
below. In addition, fluid transfer means 43 other than the examples
shown in FIGS. 4-5 may be used in connection with the treatment
apparatus 10 of the present invention, which shall not be
exclusively limited to the embodiments set forth above.
As previously indicated, the fluid transfer means 43 (e.g. the
pores 46 or membrane 54) is primarily designed to permit the
controlled flow of fluid materials (e.g. liquid medicines)
outwardly from the reservoir portion 30 of the apparatus 10.
However, under certain circumstances, the fluid transfer means 43
will permit fluid materials to enter into the reservoir portion 30
when osmotic and other physical conditions are suitable for doing
so. For example, such a situation would exist if the internal
cavity 38 of the reservoir portion 30 is provided with a supply of
mannitol crystals therein and a semi-permeable membrane 54 of the
type described above is used. Hydration of the crystals with water
will create an osmotic gradient which will draw inner ear fluids
through the selected middle-inner ear tissue structures of interest
(e.g. the round window membrane). These fluids will then be drawn
into and/or around the reservoir portion 30. It is therefore to be
understood that the fluid transfer means 43 as described herein
shall not be specifically limited to the delivery of fluid
materials from the reservoir portion 30 and likewise may include
the withdrawal of fluid materials from the middle/inner ear into
and around the reservoir portion 30 under certain
circumstances.
The multi-functional treatment apparatus 10 shown in FIGS. 1-5 may
further include an optional one-way fluid flow control valve 60
therein which is schematically illustrated in FIG. 2 within the
passageway 24 of the stem portion 14. The valve 60 is designed to
prevent the reverse flow of liquid medicines outwardly from the
internal cavity 38 of the reservoir portion 30 into the stem
portion 14. The valve 60 is particularly useful in embodiments of
the present invention which include moderately high-capacity
reservoir portions 30 with large quantities of liquid medicine
therein. The valve 60 may specifically involve numerous
commercially-available units, including but not limited to
conventional miniature ball valves and mitre valves suitable for
medical use which are known in the art, as well as a miniature
slit-type valve illustrated and generally described in U.S. Pat.
No. 4,175,563 to Arenberg which is incorporated herein by
reference. This type of valve is commercially available from Hood
Laboratories of Pembroke, Mass. (USA). The valve 60 may be retained
within the passageway 24 of the stem portion 14 by conventional
means, including but not limited to the use of adhesive materials
(e.g. commercially-available cyanoacrylate adhesive compositions,
epoxy resins, autologous fibrin glue as described in U.S. Pat. No.
4,874,368 to Miller et al. which is incorporated herein by
reference, or other conventional medical grade adhesives).
Alternatively, a valve 60 may be used which is sized to
frictionally engage the interior surface 62 of the side wall 16 of
the stem portion 14 (FIG. 2) so that the valve 60 is securely
retained therein.
Finally, as illustrated in FIGS. 1-5, the treatment apparatus 10
includes electrical potential transmission means 69 fixedly secured
to the body portion 12 for receiving electrical potentials from
middle/inner ear tissues and transmitting them out of the ear for
the detection and analysis thereof. In a preferred embodiment, the
electrical potential transmission means 69 consists of an elongate
conductive member 70 fixedly secured to the body portion 12 along
the entire length thereof as illustrated. The elongate conductive
member 70 may involve a variety of different structures. For
example, it is preferred that the elongate conductive member 70
consist of a thin wire 72 (e.g. #27 gauge) manufactured from silver
or a silver/silver chloride alloy. The wire 72 is preferably coated
with a layer 73 of insulation thereon (FIG. 1). Exemplary
insulation materials will include but not be limited to heat
shrinkable Teflon.RTM. tubing of a type well known in the art. The
wire 72 further includes a proximal end 74 and a distal end 76 as
illustrated. The wire 72 (surrounded by the layer 73 of insulation)
is fixedly secured to the body portion 12 of the apparatus 10 in
any desired or suitable position thereon. In the embodiment of
FIGS. 1-5, the wire 72 is secured to the body portion 12 of the
apparatus 10 along the underside 80 thereof (FIGS. 1-2). Attachment
may be accomplished using a medical grade adhesive of the type set
forth above (e.g. cyanoacrylate, epoxy resin, or other conventional
adhesive materials). Also, it should be noted that the conductive
member 70 may involve other structures equivalent to the wire 72.
For example, a substantially flat, flexible metallic strip (not
shown) may be used in place of the wire 72, although the wire 72 is
preferred.
With continued reference to FIGS. 1-2, the wire 72 preferably
extends around the end portion 34 of the reservoir portion 30. In
this configuration, the proximal end 74 of the conductive member 70
(e.g. wire 72) is positioned directly adjacent the reservoir
portion 30 as illustrated. Specifically, in the embodiment of FIGS.
1-2, the proximal end 74 is located at a position directly adjacent
the fluid transfer means 43 in the front portion 32 (e.g. adjacent
the fenestrated zone 44 shown FIG. 4 or the membrane 54 of FIG. 5).
In a preferred embodiment, the proximal end 74 of the wire 72
includes a conductive spherical member 86 (FIG. 1) secured thereto
(e.g. integrally formed thereon). The spherical member 86 is
optimally manufactured of the same material used to construct the
wire 72. Use of the spherical member 86 facilitates direct contact
between the wire 72 and the ear tissues of concern so that
electrical potentials therefrom may be received. In an alternative
embodiment as illustrated in FIG. 3, the proximal end 74 of the
wire 72 may include a rounded club or hook-like portion 87 thereon
instead of the spherical member 86. Thus, the proximal end 74 of
the wire 72 may encompass a variety of different forms, and shall
not be limited to any single structure or design. It should
likewise be noted that, while the conductive member 70 (e.g. the
wire 72) is primarily discussed herein as a means to receive
electrical potentials, it may also be possible to use the
conductive member 70 to apply electrical potentials to tissues of
interest in order to measure responsive stimuli therefrom. Thus,
the conductive member 70 of the present invention shall not be
exclusively limited to the receipt of electrical potentials.
The distal end 76 of the wire 72 preferably extends beyond the open
first end 20 of the stem portion 14 as illustrated. Upon insertion
of the treatment apparatus 10 into the middle ear of a patient, the
distal end 76 of the wire 72 will pass through the incised tympanic
membrane (or beneath a surgically formed tympanomeatal flap as
described below), through the external auditory canal of the
patient, and will ultimately extend outwardly from the patient's
ear. In this regard, the distal end 76 is then readily connected to
an external monitoring apparatus 90 (FIG. 2) of conventional design
which collects and characterizes resting or evoked electrical
potentials ultimately received from the inner ear. Further
information regarding the monitoring apparatus 90 will be described
below.
As indicated herein, the conductive member 70 is especially
designed to receive electrical potentials from selected inner ear
tissues. This capability is particularly useful in connection with
a process known as "ECoG" which is an abbreviation for
"electrocochleography". Electrocochleography is a known technique
for measuring electrical potentials from the inner ear which
basically involves measurement of the whole nerve-cochlear action
potential (hereinafter "AP"). Alternatively, ECoG can be used to
indirectly measure hair cell electrical activity. ECoG can further
be used to measure the summating potential (hereinafter "SP")
within the inner ear in response to externally generated clicks,
tone bursts, and/or pips. The SP is basically a D.C. distortion
potential which can indicate the amount of distortion in the
cochlear duct associated with endolymphatic hydrops or other
changes in the inner ear. The relative amount of distortion may be
expressed either as an SP/AP ratio (in response to
externally-generated clicks, etc.), or as an absolute measurement
in response to specific, externally-generated tone bursts and the
like. Cochlear microphonics can also be measured as well as
otoacoustic emissions (hereinafter "OAE") in order to assess hair
cell function or dysfunction. Finally, endocochlear potentials can
be measured using the components described herein if selected
portions of the conductive member 70 are operatively positioned
within the cochlea rather than outside of the cochlea. Further
information on ECoG is presented in Portmann, M.,
"Electrophysiological correlates of endolymphatic hypertension and
endolymphatic hydrops: an overview of electrocochleography (ECoG)",
Proceedings of the Third International Symposium and Workshops on
the Surgery of the Inner Ear, Snowmass, Col. (USA) Jul. 29-Aug. 4,
1990 as reported in Inner Ear Surgery, edited by I. Kaufman
Arenberg, Kugler Publications, Amsterdam/New York, pp. 241-247
(1991) which is incorporated herein by reference.
As stated herein, the conductive member 70 (e.g. wire 72) is
especially useful in connection with conventional ECoG procedures.
Resting or evoked electrical potentials received by the wire 72
through direct contact of the proximal end 74 (e.g. the spherical
member 86 or hook-like portion 87) with selected ear tissues are
routed through the wire 72 to the distal end 76 which is
operatively connected (using conventional electrical connecting
clips and the like) to the monitoring apparatus 90 as stated above.
An exemplary monitoring apparatus 90 suitable for use herein
consists of commercially available ECoG detection systems sold
under the names "Viking II.TM." and "Spirit.TM." by Nicolet, Inc.
of Madison, Wis. (USA). However, a wide variety of different,
commercially-available systems may be used to receive and quantify
electrical potentials from the conductive member 70 (e.g. wire 72),
including but not limited to computer-monitored voltage
amplifier/analog-to-digital converter units known in the art. As
noted above, the wire 72 is sufficiently long to enable the distal
end 76 thereof to terminate at a position outside of the patient's
ear. As a result, attachment of the distal end 76 of the wire 72 to
the monitoring apparatus 90 is greatly facilitated. In a preferred
and optimum embodiment, the total length of the wire 72 from the
proximal end 74 to the distal end 76 (measured when straight) will
be about 5.0 cm.
In order to use the treatment apparatus 10 as described above, the
apparatus 10 is surgically inserted within the middle ear of a
patient so that the reservoir portion 30 is positioned entirely
within the middle ear and against a selected middle-inner ear
interface tissue structure (e.g. the round window membrane).
Insertion into the middle ear may be accomplished through an
incision in the tympanic membrane (ear drum) or beneath a
surgically formed tympanomeatal flap formed using conventional
tympanotomy procedures as described in greater detail below. During
insertion, the apparatus 10 is manipulated so that the fluid
transfer means 43 (e.g., the fenestrated zone 44 [pores 46] or the
membrane 54) is positioned against and in direct contact with the
selected interface tissue structures. Furthermore, in accordance
with the insertion techniques set forth herein, at least part of
the stem portion 14 (e.g. the open first end 20) is positioned so
that it will extend through the incised tympanic membrane or
tympanomeatal flap and into the external auditory canal of the
patient. When the medicine delivery apparatus 10 is positioned in
this orientation, the reservoir portion 30 may be readily refilled
with liquid medicines (or supplied with different medicines)
through the external auditory canal and stem portion 14 without
additional surgical intervention or removal of the apparatus 10.
This is accomplished through the use of a conventional syringe
apparatus or other comparable device as described in further detail
below. Likewise, if the reservoir portion 30 includes solid (e.g.
crystalline) or gel-type precursor medicine materials therein,
additional liquid (e.g. water, saline solution, or the like) may be
added as necessary or appropriate through the stem portion 14 and
external auditory canal using the above-described syringe or other
selected external fluid delivery system. In addition, the apparatus
10 is positioned/manipulated so that the proximal end 74 of the
wire 72 is in direct physical contact with the interface tissue
structures of concern (e.g. the round window membrane). As a
result, electrical potentials may be received therefrom. This is
readily accomplished through the use of wire 72 wherein the
proximal end 74 (with the spherical member 86 or hook-like portion
87 thereon) is placed in direct physical contact with the selected
interface tissues. Contact between the proximal end 74 of the wire
72 and the selected tissue materials is readily accomplished since
the proximal end 74 is adjacent the front portion 32 of the
reservoir portion 30 (e.g. adjacent the fenestrated zone 44 or
membrane 54) as previously indicated.
In order to insert the medicine delivery apparatus 10 within the
ear of a patient, a number of different minimally-invasive surgical
techniques may be used. Accordingly, the present invention shall
not be limited to the use of any specific surgical techniques. For
example, as previously noted, the treatment apparatus 10 may be
surgically inserted in accordance with a middle ear exploration via
a tympanomeatal flap exposing the middle ear cleft and ossicular
chain. The fluid transfer means 43 (e.g. the fenestrated zone 44
[pores 46] or the membrane 54) associated with the reservoir
portion 30 of the medicine apparatus 10 is placed in contact with
and against the round window membrane in the bony round window
niche. In this orientation, the proximal end 74 (including the
spherical member 86 or hook-like portion 87) of the wire 72 will
likewise be in direct contact with the round window membrane. This
will occur due to the close proximity of the proximal end 74 of the
wire 72 with the fluid transfer means 43 as indicated above. The
stem portion 14 of the apparatus 10 is then brought through the
otherwise intact tympanic membrane via a tympanotomy incision in
the posterior inferior portion of the tympanic membrane. The
above-described construction materials used to produce the
apparatus 10 are sufficiently soft, flexible, and collapsible so
that the entire apparatus 10 can be easily removed through the
tympanotomy incision when removal of apparatus 10 is desired (e.g.
normally after about 4-8 weeks). In addition, the apparatus 10 may
be retained in position within the middle ear through the use of a
selected adhesive applied to one or more portions of the apparatus
10. The adhesive should consist of a biocompatible material which
is readily detachable from the materials adhered thereto. An
exemplary adhesive suitable for this purpose involves an autologous
fibrin glue as described above.
As previously stated, the treatment apparatus 10 has wide
applicability in treating various inner ear tissues, tissue
regions, and fluid compartments. Placement of the apparatus 10
against suitable middle-inner ear interface tissues (e.g. the round
window membrane) will enable the delivered liquid medicines to pass
directly therethrough and come in contact with various inner ear
tissues and fluid compartments including but not limited to the
cochlea, vestibular labyrinth, endolymphatic sac, endolymphatic
duct, and the membranous endolymphatic/perilymphatic system.
Passage of liquid materials through the round window membrane is
possible in view of its minimal thickness and specific permeable
physiological character. Likewise, a wide variety of liquid
medicines/therapeutic agents may be used in connection with the
apparatus 10, including but not limited to urea, mannitol,
sorbitol, sodium chloride, steroids, heparin, hyaluronidase,
aminoglycoside antibiotics (streptomycin/gentamycin), glycerol,
xylocaine, immunoglobulins, and other antibiotic, biological, or
antimicrobial materials. Furthermore, as previously noted, the
reservoir portion 30 of the medicine delivery apparatus 10 may be
initially supplied with solid (e.g. crystalline), gel-type, viscous
liquid, or powdered precursor medicine materials which can be
hydrated/solvated in situ in order to produce liquid medicine
materials. Exemplary solid or gel-type/viscous medicine materials
to which water may be added in this manner include but are not
limited to mannitol crystals, sodium chloride crystals, viscous
liquid glycerol, powdered streptomycin/gentamycin, hyaluronidase
gel and the like. Accordingly, the present invention shall not be
limited to the delivery of any specific chemical materials,
biological compositions, pharmaceuticals, or therapeutic
agents.
FIG. 9 is a schematic, partial cross-sectional view of the ear 149
of a human subject illustrating the treatment apparatus 10 of FIG.
1 inserted therein. As shown, the apparatus 10 is positioned so
that the reservoir portion 30 is entirely within the middle ear,
generally designated in FIG. 9 at reference number 150. The inner
ear region is generally designated in FIG. 9 at reference number
151, and further includes the cochlea 152 and the endolymphatic sac
153, as well as the endolymphatic duct 154 associated therewith.
The round window membrane is generally designated at reference
number 155, and constitutes an interface tissue structure between
the middle ear 150 and the inner ear region 151.
In FIG. 9, the reservoir portion 30 is specifically positioned so
that the fluid transfer means 43 (e.g. the fenestrated zone 44) is
adjacent to and in direct physical contact with the round window
membrane 155 in the middle ear 150. Contact between the pores 46 of
the fenestrated zone 44 and the round window membrane 155 causes
liquid medicines within the internal cavity 38 of the reservoir
portion 30 (FIG. 2) to be drawn by capillary action through the
pores 46 and thereafter onto the round window membrane 155. The
liquid medicines then diffuse through the round window membrane 155
and into the inner ear region 151 for the treatment of tissues,
fluids, fluid compartments, and tissue regions therein. Once again,
it should be noted that the present invention shall not be limited
to the treatment of any specific inner ear tissues, structures, or
compartments.
Alternatively, if the embodiment of FIG. 5 were used, the
semi-permeable membrane 54 (or the micropore filter structures used
in connection with other embodiments) would be positioned adjacent
to and in direct contact with the round window membrane 155. Direct
physical contact between the membrane 54 of the reservoir portion
30 and the round window membrane 155 again causes liquid medicines
within the internal cavity 38 of the reservoir portion 30 to be
drawn through the membrane 54 by capillary action and/or osmotic
forces. The liquid medicines subsequently come in contact with the
round window membrane 155, and are then able to diffuse
therethrough into the inner ear 151.
With continued reference to FIG. 9, the proximal end 74 and the
spherical member 86 associated with the conductive member 70 is
positioned adjacent to and in direct contact with the round window
membrane 155 so that electrical potentials may be received
therefrom as noted above. As previously indicated, such potentials
may be produced within the inner ear 151 using externally generated
tone bursts, pips and the like in accordance with standard ECoG
procedures. These potentials travel through the inner ear 151 and
thereafter to the round window membrane 155 where they are received
by the wire 72. The distal end 76 of the wire 72 preferably passes
through an incision 158 in the tympanic membrane 159, and is
positioned outwardly from the ear 149 as illustrated. The distal
end 76 of the wire 72 is then connected using a standard miniature
connecting clip 160 to ECoG monitoring apparatus 90 via electrical
conduit or wire 161. The monitoring apparatus 90 is used to analyze
and quantify electrical potentials (e.g. ECoG potentials) received
from the inner ear 151 in response to various stimuli or as an
indication of resting potential activity.
Finally, as shown in FIG. 9, a substantial section 162 of the stem
portion 14 resides within the external auditory canal 166 of the
ear 149 adjacent the tympanic membrane 159 and remotely spaced from
the middle ear 150. As noted above, the tympanic membrane 159
preferably has an incision 158 therein which allows the passage of
both the conductive member 70 and the stem portion 14 therethrough.
Alternatively, the section 162 of the stem portion 14 may pass
beneath a tympanomeatal flap (not shown) depending on the
techniques chosen by the surgeon. In order to supply the internal
cavity 38 of the reservoir portion 30 with liquid medicines (or
hydrating fluids designed to produce liquid medicines in situ), a
conventional syringe 170 having a hollow needle 172 (e.g. #27
gauge) attached thereto is used. As far as liquid medicines are
concerned, such materials are supplied to the internal cavity 38 of
the reservoir portion 30 immediately after insertion of the
treatment apparatus 10 within the ear 149, when initial supplies of
liquid medicine within the reservoir portion 30 have been depleted,
or when changes to previously-administered medication are
necessary. Specifically, the syringe 170 is first filled with the
selected liquid medicine. The needle 172 is thereafter carefully
inserted into the external auditory canal 166, and into the open
first end 20 of the stem portion 14. Thereafter, pressure is
exerted on the plunger 176 of the syringe 170 to deliver the
selected liquid medicine (or other fluid materials of interest)
from the syringe 170 through the needle 172 into the stem portion
14. The liquid medicine then flows from the stem portion 14 through
the valve 60 (if used) and into the internal cavity 38 of the
reservoir portion 30. If valve 60 is used, it will permit liquid
medicine to flow from the stem portion 14 into the reservoir
portion 30, but will prevent the reverse flow of fluid outwardly
from the reservoir portion 30 back into the stem portion 14. It
should be noted that refilling of the reservoir portion 30 with the
same or different liquid medicines may be undertaken at selected
time intervals as determined by preliminary pilot studies or
changes in clinical symptoms as indicated by, for example, ECoG
analysis. Such time intervals will vary, depending on the size and
volume characteristics of the treatment apparatus 10 being used, as
well the type and severity of the clinical problems to be treated.
In any event, refilling in the foregoing manner is accomplished in
a rapid, non-invasive manner (e.g. while the reservoir portion 30
is maintained against the round window membrane 155) without the
need for additional invasive surgery.
Furthermore, as noted above, the reservoir portion 30 may be
initially provided with a supply of a solid crystalline), powdered,
or gel-type medicine precursor material which may be
hydrated/solvated to produce liquid medicine materials in situ
after placement of the apparatus 10 in the ear 149 shown in FIG. 9.
Fluid (e.g. water or saline solution) addition is typically
accomplished in the same manner set forth above using the syringe
170 and needle 172.
Finally, instead of the syringe 170 and needle 172, other
commercial fluid delivery systems (not shown) may be used to
deliver liquid materials (e.g. water, saline solution, medicines or
other hydrating agents) to the reservoir portion 30 of the
apparatus 10. An exemplary commercial fluid delivery system
suitable for this purpose would involve a product which is known as
an osmotic pump. Such a pump is described in Kingma, G. G., et al.,
"Chronic drug infusion into the scala tympani of the guinea pig
cochlea", Journal of Neuroscienc Methods, 45:127-134 (1992) which
is incorporated herein by reference. An exemplary, commercially
available osmotic pump may be obtained from the Alza Corp. of Palo
Alto, Calif. (USA) and is further generally described in U.S. Pat.
Nos. 4,320,758 and 4,976,966. However, it should noted that the
present invention shall not be limited to any particular type of
delivery system. In fact, other comparable fluid delivery systems
may be used in connection with all embodiments of the
invention.
An alternative multi-functional treatment apparatus 200 is
illustrated in FIGS. 6-8. Specifically, the apparatus 200 includes
a body portion 202 which, as noted above, is preferably of unitary
(e.g. single-piece), molded construction. In a preferred
embodiment, the body portion 202 is manufactured of a soft,
resilient, flexible (e.g. stretchable), and inert material. The
flexibility, elasticity, and softness of the body portion 202 is
again of particular importance in order to avoid damage to delicate
inner ear tissues during the insertion thereof into a patient.
Exemplary construction materials suitable for this purpose are the
same as those listed above with respect to the treatment apparatus
10. In addition, in certain instances, it may likewise be desirable
to manufacture all or part of the body portion 202 from medical
grade silicone rubber (or materials equivalent thereto) impregnated
with a radiopaque agent (e.g. BaSO.sub.4) which will render all or
part of the body portion 202 radiopaque during the application of
X-rays.
With continued reference to FIGS. 6-8, the body portion 202 further
includes a tubular first stem portion 204. As shown in FIG. 7, the
first stem portion 204 includes a continuous side wall 206 which is
preferably annular (e.g. ring-like) in cross-section. The first
stem portion 204 further includes an open first end 208, a second
end 210, and a passageway 212 extending continuously through the
first stem portion 204 from the open first end 208 to the second
end 210 (FIG. 7). In a preferred embodiment, the first stem portion
204 will have diameter "D.sub.2 " which is uniform along the entire
length thereof from the open first end 208 to the second end 210.
Optimally, for use in the human ear, the diameter "D.sub.2 " of the
first stem portion 204 will be about 0.2-2.0 mm. It should again be
noted that this diameter range (as well as other quantitative
specifications set forth below) is for example purposes only, and
the present invention shall not be limited to any particular sizes
or dimensions. Furthermore, the length "L.sub.5 " (FIG. 6) of the
first stem portion 204 will preferably be about 0.3-1.5 mm.
With continued reference to FIGS. 6-7, the second end 210 of the
first stem portion 204 is operatively and fixedly connected to an
enlarged reservoir portion 220 which is designed to retain a supply
of liquid medicine therein. As indicated above, it is preferred
that the body portion 202 of the treatment apparatus 200 be of
unitary (e.g. single-piece) construction. In this regard, the first
stem portion 204 and the reservoir portion 220 are, in a preferred
embodiment, integrally formed together during production of the
apparatus 200. The reservoir portion 220 may involve numerous
different external configurations. With reference to FIGS. 6-8, the
reservoir portion 220 is configured in an oval (e.g. ovoid) shape.
However, the reservoir portion 220 may also resemble a sphere or
other comparable configuration. In this regard, the reservoir
portion 220 of the apparatus 200 shall not be limited to any
particular external shape. As illustrated in FIG. 7, the reservoir
portion 220 further includes an internal cavity 230 therein which
is adapted to receive liquid medicines, solid crystalline)
medicines, gel-type medicines or other therapeutic agents as
described in greater detail below. An exemplary supply of liquid
medicine within the internal cavity 230 is illustrated at reference
number 231 in FIG. 7. The internal cavity 230 is surrounded by an
external wall 232 as illustrated. While the volumetric capacity of
the internal cavity 230 may be suitably varied during manufacture
of the medicine delivery apparatus 200, it is preferred that the
cavity 230 have a capacity of about 3.0-6.0 ml. Furthermore, as
illustrated in FIG. 6, it is preferred that the reservoir portion
220 have a length "L.sub.6 " of about 3.0-8.8 mm, and a thickness
"T.sub.2 " of about 1.0-8.7 mm.
As illustrated in FIGS. 6-7, the body portion 202 also includes a
tubular second stem portion 236 which, in a preferred embodiment is
substantially identical in structure to the first stem portion 204.
However, as indicated below, it is preferred that the second stem
portion 236 be longer than the first stem portion 204. With
reference to FIG. 7, the second stem portion 236 includes a
continuous side wall 240 which is preferably annular (e.g.
ring-like) in cross-section. The second stem portion 236 further
includes an open first end 242 (FIGS. 6-7), a second end 244, and a
passageway 245 extending continuously through the second stem
portion 236 from the first end 242 to the second end 244. In a
preferred embodiment, the second stem portion 236 will have a
diameter "D.sub.3 " which is uniform along the entire length
thereof from the open first end 242 to the second end 244.
Optimally, for use of the apparatus 200 in the human ear, the
diameter "D.sub.3 " will be about 0.2-2.0 mm. Furthermore, the
length "L.sub.7 " (FIG. 6) of the second stem portion 236 will
preferably be about 8.8-23.8 mm. The overall length "L.sub.8 " of
the body portion 202 in the present embodiment will preferably be
about 12.1-34.1 mm which will readily enable placement of the
apparatus 200 within the ear of a patient as described in greater
detail below.
The second end 244 of the second stem portion 236 is operatively
connected and fixedly secured to (e.g. integrally formed with) the
reservoir portion 220 in the same manner set forth above with
respect to the first stem portion 204. As shown in FIG. 7,
attachment of the second end 210 of the first stem portion 204 and
the second end 244 of the second stem portion 236 to the reservoir
portion 220 in the foregoing manner enables the passageways 212,
245 in the first and second stem portions 204, 236 to be in fluid
communication with the internal cavity 230 of the reservoir portion
220.
So that the medicine delivery apparatus 200 may be readily inserted
within the ear of a patient, the first stem portion 204 is
positioned on a first side 250 of the reservoir portion 220 and the
second stem portion 236 is positioned on a second side 252 of the
reservoir portion 220 (FIG. 6). As shown in FIGS. 6-7, the first
side 250 and the second side 252 are directly opposite each other.
As a result, the first stem portion 204 will preferably be in axial
alignment with the second stem portion 236 as illustrated. With
reference to FIG. 7, the first stem portion 204 will have a
longitudinal axis "A.sub.1 " which is in alignment with (e.g.
collinear with) the longitudinal axis "A.sub.2 " of the second stem
portion 236 so that the first stem portion 204 is positioned at a
180.degree. angle relative to the second stem portion 236.
It should also be noted that the treatment apparatus 200 may
optionally include at least one fluid flow control valve 260
therein which is schematically illustrated in FIG. 7. The valve 260
may be positioned within the passageway 212 of the first stem
portion 204, within the passageway 245 of the second stem portion
236, or within both of the passageways 212, 245. If positioned
within the passageway 212 of the first stem portion 204, the valve
260 will enable one-way fluid flow from the reservoir portion 220
to the first stem portion 204 and outwardly therefrom, while
preventing tissue fluids and the like from entering the first stem
portion 204 and passing into the reservoir portion 220. If
positioned within the passageway 245 of the second stem portion
236, the valve 260 will prevent the reverse flow of liquid
medicines outwardly from the reservoir portion 220 into the second
stem portion 236. While FIG. 7 illustrates the use of a valve 260
positioned within the passageway 245 of the second stem portion
236, it is to be understood that the present invention shall not be
limited exclusively to the use of a single valve 260 as shown, and
may likewise encompass the placement of a valve 260 within the
passageway 212 of the first stem portion 204. The valve 260 (as
used in passageway 212 and/or passageway 245) will be especially
useful in embodiments of the present invention which include
reservoir portions 220 which contain substantial quantities of
liquid medicine therein. The valve 260 may involve numerous
commercially-available units including but not limited to the types
described above with respect to valve 60. Once again, the present
invention shall not be limited in any manner regarding the type of
valve 260 which can be used which may also be pressure-sensitive
(e.g. capable of allowing fluids therethrough only if they exert a
pre-designated fluid pressure on the valve). The valve 260 (if
used) may be retained within the passageway 212 and/or passageway
245 by conventional means, including but not limited to those
described above with respect to valve 60 (e.g. the use of adhesives
or frictional engagement within passageway 212 and/or passageway
245).
Finally, as illustrated in FIG. 7, the treatment apparatus 200
includes electrical potential transmission means 261 fixedly
secured to the body portion 202 for receiving electrical potentials
from the inner/middle ear and transmitting them out of the ear for
the detection and analysis thereof. In a preferred embodiment, the
electrical potential transmission means 261 consists of an elongate
conductive member 270 fixedly secured to the body portion 202 as
illustrated. The elongate conductive member 270 is substantially
identical to the conductive member 70 described above, and may
involve a variety of different structures. For example, it is
preferred that the elongate conductive member consist of a thin
wire 272 manufactured from the same materials used to construct
wire 72. The wire 272 (e.g. of the same general type and gauge as
wire 72) includes a proximal end 274 and a distal end 276
illustrated in FIG. 6. The wire 272 is fixedly secured to the body
portion 202 of the apparatus 200 in any desired or suitable
position thereon. In the embodiment of FIGS. 6-7, the elongate
conductive member 270 (e.g. wire 272) is secured to the body
portion 202 of the apparatus 200 along the lower surface 279
thereof. Attachment may be accomplished using an adhesive of the
type set forth above relative to attachment of the conductive
member 70 to the treatment apparatus 10 (e.g. a conventional
cyanoacrylate or epoxy resin adhesive). Furthermore, the wire 272
is preferably coated with a layer 280 of an insulating material.
Exemplary insulating materials include but are not limited to heat
shrinkable Teflon.RTM. coating materials known in the art. Also, as
described above with respect to the conductive member 70, it should
be noted that the conductive member 270 may involve other
structures equivalent to the wire 272 including but not limited to
the use of a relatively flat, flexible metallic strip (not
shown).
With continued reference to FIGS. 6-7, the proximal end 274 of the
wire 272 is preferably positioned adjacent the second end 210 of
the first stem portion 204 (e.g. at the juncture 281 between the
first stem portion 204 and the reservoir portion 220 as shown in
FIG. 6). Alternatively, the proximal end 274 of the wire 272 may be
positioned adjacent the open first end 208 of the first stem
portion 204, although the previously described orientation is
preferred. Likewise, in a preferred embodiment, the proximal end
274 of the wire 272 includes a conductive spherical member 286
secured thereto (e.g. integrally formed thereon) optimally
manufactured of the same material used to construct the wire 272.
Use of the spherical member 286 facilitates direct contact between
the wire 272 and ear tissues of concern so that electrical
potentials (ECoG potentials) may be received therefrom. It should
likewise be noted that while the conductive member 270 (e.g. wire
272) is discussed herein with reference to the receipt of
electrical potentials, it may also be possible to use the
conductive member 270 to apply electrical potentials to tissues of
interest in order to measure responsive stimuli therefrom. Thus,
the conductive member 270 (e.g. wire 272) of the present invention
shall not be exclusively limited to the receipt of electrical
potentials.
In an alternative embodiment as illustrated fin FIG. 10, the
proximal end 274 of the wire 272 may include a rounded club or
hook-like portion 289 instead of the spherical member 286. Thus,
the proximal end 274 of the wire 272 may encompass a variety of
different forms, and shall not be limited to any single structure
or design. In addition, as illustrated in FIG. 6, the distal end
276 of the wire 272 preferably extends beyond the open first end
242 of the second stem portion 236 as illustrated. Upon insertion
of the apparatus 200 into the ear of a patient, the distal end 276
of the wire 272 will preferably pass through the incised tympanic
membrane, along the external auditory canal of the patient, and
will preferably terminate at a position outside of the patient's
ear. When oriented in this manner, the distal end 276 is readily
connected to an external monitoring apparatus 290 (FIG. 7) of
conventional design which may be used to analyze and quantify
electrical potentials from the inner ear. In a preferred
embodiment, the monitoring apparatus 290 is of the same type as
monitoring apparatus 90. Furthermore, as previously described with
respect to the conductive member 70, the conductive member 270 is
designed to receive resting or evoked electrical potentials from
inner ear tissues in accordance with known ECoG procedures. Thus,
all of the information, techniques, and materials set forth above
regarding use of the conductive member 70 for ECoG purposes is
equally applicable to the conductive member 270. In a preferred and
optimum embodiment, the total length of the wire 272 from the
proximal end 274 to the distal end 276 (measured when straight)
will be about 5.0 cm.
The treatment apparatus 200 of the present invention is used in a
somewhat different manner compared with the apparatus 10.
Specifically, the apparatus 200 is surgically inserted within the
ear of a patient so that the first stem portion 204 (e.g. at least
the open first end 208 thereof) is positioned within the inner ear.
Specifically, the open first end 208 of the first stem portion 204
will be positioned against and in direct contact with the inner ear
tissues/tissue regions to be treated so that liquid medicines from
the internal cavity 230 of the reservoir portion 220 may be drawn
outwardly therefrom and through the first stem portion 204 by
capillary action (described in greater detail below). It is
likewise preferred that the reservoir portion 220 be positioned
entirely within the middle ear as described below. Furthermore, at
least a section of the second stem portion 236 (including the open
first end 242 thereof) is preferably positioned so that it will
extend through the incised tympanic membrane and into the external
auditory canal of the patient at a location remotely spaced from
the middle ear. In this manner, the reservoir portion 220 may be
readily supplied with liquid medicines or other fluid materials as
needed through the external auditory canal and second stem portion
236 without additional surgical intervention in most instances. In
addition, the treatment apparatus 200 is manipulated during or
after insertion so that the proximal end 274 (e.g. spherical member
286) of the elongate conductive member 270 (e.g. wire 272) is in
direct physical contact with the ear tissues of concern so that
electrical potentials may be received therefrom as described in
further detail below.
FIG. 11 is a schematic, partial cross-sectional view of the ear 300
of a human subject illustrating the apparatus 200 of FIG. 6
inserted therein. As shown, the apparatus 200 is positioned so that
the reservoir portion 220 is entirely within the middle ear
(generally designated in FIG. 11 at reference number 302). The
first stem portion 204 (and the open first end 208 thereof) is
positioned within the inner ear (generally designated in FIG. 11 at
reference number 303) which includes the cochlea 304, the
endolymphatic sac 305, and the endolymphatic duct 307. As described
below, the first stem portion 204 is positioned within an opening
309 formed through the stapes footplate 310 and oval window 312
thereunder. As a result, the first end 208 of the first stem
portion 204 may come in direct physical contact with the inner ear
tissues, fluids, and/or tissue regions of concern so that liquid
medicine materials from the reservoir portion 220 may be delivered
thereto by capillary action through the passageway 212 of the first
stem portion 204 and out of the open first end 208 thereof.
With continued reference to FIG. 11, the spherical member 286
associated with the proximal end 274 of the conductive member 270
is positioned adjacent to and in direct contact with the stapes
footplate 310 in the middle ear (and other tissues associated
therewith) so that electrical potentials originating within the
inner ear 303 may be received therefrom. In an alternative
embodiment, if the proximal end 274 and spherical member 286 are
positioned adjacent the open first end 208 of the first stem
portion 204, then these components will come in direct contact with
inner ear tissues of concern. As indicated above, such potentials
may be generated using externally generated tone bursts, clicks,
pips and the like in accordance with standard ECoG procedures. The
distal end 276 of the wire 272 associated with the conductive
member 270 (which may have a portion of the layer 280 of insulating
material removed therefrom outside of the ear 300) is positioned
outwardly from the ear 300 as illustrated. The distal end 276 is
thereafter connected using a standard miniature connecting clip 320
to monitoring apparatus 290 via conductive conduit 322. The
monitoring apparatus 290 is used to analyze and quantify electrical
potentials ultimately received from the inner ear 303.
Finally, as shown in FIG. 11 and indicated above, a substantial
section 323 of the second stem portion 236 (including the open
first end 242 thereof) passes through an incision 325 in the
tympanic membrane 324 and resides within the external auditory
canal 330 of the ear 300. Alternatively, the section 323 of the
second stem portion 236 may pass beneath a tympanomeatal flap (not
shown) depending on the techniques chosen by the surgeon. In order
to supply the internal cavity 230 of the reservoir portion 220 with
liquid medicines (e.g. immediately after insertion of the treatment
apparatus 200, when initial supplies of liquid medicine within the
reservoir portion 220 have been depleted, or when a change in the
type of delivered medicine is desired), a conventional syringe 350
having a hollow needle 352 attached thereto is used in the same
manner described above with respect to treatment apparatus 10 and
syringe 170. Specifically, the syringe 350 is initially filled with
a selected liquid medicine. The needle 352 is thereafter inserted
into the external auditory canal 330 and through the open first end
242 of the second stem portion 236. Next, pressure is exerted on
the plunger 356 of the syringe 350 in order to deliver the liquid
medicine from the syringe 350 through the needle 352 and into the
second stem portion 236. The liquid medicine thereafter flows from
the second stem portion 236 through the valve 260 (if used) and
into the reservoir portion 220. If valve 260 is used, it will
permit liquid medicine to flow from the second stem portion 236
into the reservoir portion 220, but will prevent the reverse flow
of fluid outwardly from the reservoir portion 220 back into the
second stem portion 236. It should again be noted that refilling of
the reservoir portion may be undertaken at selected time intervals
as determined by preliminary pilot studies or changes in clinical
symptoms as indicated by, for example, ECoG analysis. In any event,
refilling in the foregoing manner is accomplished in a rapid,
non-invasive manner without the need for additional surgery.
In addition, as noted above, the reservoir portion 220 may be
initially provided with a supply of a solid (e.g. crystalline),
powdered, or gel-type medicine material which may be
hydrated/solvated to produce liquid medicines in situ after
placement of the apparatus 200 in the ear 300 shown in FIG. 11. The
addition of a selected fluid (e.g. water, saline solution, or the
like) is typically accomplished in the same manner set forth above
using the syringe 350 and needle 352. Specifically, an additional
supply of therapeutic agents or liquid medicine materials may be
delivered through the external auditory canal 330 into the first
end 242 of the second stem portion 236 of the apparatus 200 using
the syringe 350 and the needle 352. In a preferred embodiment, this
activity takes place while the reservoir portion 230 is maintained
within the middle ear 302 and the first end 208 of the first stem
portion 204 is maintained within the inner ear 303. It should also
be noted that alternative fluid delivery devices may be used in
connection with the apparatus 200 other than syringe 350 including
but not limited to the osmotic pump systems described above
relative to apparatus 10.
With respect to surgical insertion of the treatment apparatus 200,
a number of different approaches may be used, and the present
invention shall not be limited to any specific surgical technique.
However, an exemplary technique for inserting the apparatus 200 so
that it is positioned as illustrated in FIG. 11 would first involve
exploration of the middle ear 302 via a tympanomeatal flap exposing
the middle ear cleft and the ossicular chain. The stapes footplate
310 (and underlying oval window 312) is then fenestrated to form
opening 309 therethrough using a conventional microdrill unit or
standard medical laser system (e.g. involving a
commercially-available CO.sub.2 laser, an argon laser, or a tunable
dye laser). The opening 309 as described above functions as an
access port in the ear between the middle ear 302 and the inner ear
303. The apparatus 200 is then positioned within the middle ear
302, and the first stem portion 204 placed through the opening 309
in the stapes footplate 310 and oval window 312. Alternatively, the
first stem portion 204 may be placed through a similar opening
(access port) formed in the same manner through the bony cochlear
or vestibular labyrinth. Thus, the present invention shall not be
limited to any particular location with respect to the opening 309
which may be placed in any suitable position so that access can be
made from the middle ear 302 to the inner ear 303.
As noted above, all or part of the apparatus 200 may be made
radiopaque by impregnation thereof with a marker composition (e.g.
BaSO.sub.4 or other comparable material) during production of the
apparatus 200. In a preferred and optimum embodiment, only the
first stem portion 204 will be impregnated with the marker
composition so that the first stem portion 204 within the inner ear
303 may be readily identified and distinguished from the remainder
of the apparatus 200. Upon insertion of the first stem portion 204
of the apparatus 200 into the inner ear 303, the first stem portion
204 may come in contact with a variety of inner ear tissue/fluid
materials including but not limited to the perilymph (an inner ear
fluid which is low in potassium ions and high in sodium ions), the
saccular membrane, the endolymph (an inner ear fluid which is low
in sodium ions and high in potassium ions), and the internal
structures of the cochlea or vestibular labyrinth. The apparatus
200 may then be used to deliver needed liquid medicine materials to
these structures in a highly efficient and sustained manner. As
noted above, it is preferred that any fluid materials within the
apparatus 200 be present in a sufficient quantity so that they will
entirely fill at least the reservoir portion 220 and the first stem
portion 204. As a result, such fluid materials will be present at
the open first end 208 of the first stem portion 204. When the
first end 208 of the first stem portion 204 is placed in direct
contact with the selected inner ear tissues by surgical
manipulation of the apparatus 200, fluid materials will be drawn
therefrom by capillary action.
Finally, it should be noted that the treatment apparatus 200 may be
selectively modified to include various additional components which
shall be encompassed within the scope of this invention. For
example, as illustrated in FIG. 12, the apparatus 200 is modified
to include an additional grouping of components thereon to produce
an alternative treatment apparatus 400. All of the information,
techniques, and characteristics set forth above regarding the
apparatus 200 are equally applicable to the apparatus 400 except as
otherwise indicated below.
In the embodiment of FIG. 12, the apparatus 400 includes an
additional reservoir portion and at least one additional tubular
stem portion. For example, operatively connected to and fixedly
secured to the first end 208 of the first stem portion 204 is a
second reservoir portion 401 which is comparable in function,
structure, and construction to the reservoir portion 220 (which, in
this embodiment, shall be deemed the first reservoir portion 220).
The second reservoir portion 401 includes an internal cavity 402
therein which is substantially identical in configuration and
capacity to cavity 230 in the first reservoir portion 220. In
accordance with this embodiment, the passageway 212 in the first
stem portion 204 is in fluid communication with the internal cavity
402 as shown. It should be noted that, in this embodiment, the
first and second reservoir portions 220, 401 may each have optional
fluid transfer means therein (not shown) of the same general type
described above with respect to fluid transfer means 43 in
apparatus 10.
Extending outwardly from the second reservoir portion 401 at
position 404 thereon is an additional tubular stem portion
(hereinafter designated as third stem portion 406) having an open
first end 408, a second end 410, and a passageway 412 extending
continuously through the third stem portion 406 from the open first
end 408 to the second end 410. The passageway 412 is in fluid
communication with the internal cavity 402 of the second reservoir
portion 401. In a preferred embodiment, the third stem portion 406
is substantially identical in structure, function, and size to the
first stem portion 204 as described above.
Extending outwardly from the second reservoir portion 401 at
position 420 thereon is an even further additional tubular stem
portion (e.g. hereinafter designated as fourth stem portion 422)
having an open first end 424, a second end 426, and a passageway
430 extending continuously through the fourth stem portion 422 from
the open first end 424 to the second end 426 thereof. The
passageway 430 is in fluid communication with the internal cavity
402 of the second reservoir portion 401. Otherwise, the fourth stem
portion 422 is substantially identical in structure, function, and
size to the first stem portion 204 as described above. One or more
of the third and fourth stem portions 406, 422 may include at least
one valve 438 therein as shown in FIG. 12 which illustrates a
single valve 438 positioned within the fourth stem portion 422. The
valve 438 is preferably of the same type and configuration as the
valves 60, 260 described above, and is mounted/positioned within
third and/or fourth stem portions 406, 422 in the same manner
described herein relative to valves 60, 260. One or more of the
third and fourth stem portions 406, 422 may be made radiopaque
during production of the alternative treatment apparatus 400 by the
incorporation of a marker composition therein (e.g. BaSO.sub.4 or
other comparable material). In addition, at least one valve (not
shown) of the same type as valve 438 may be positioned within the
internal cavity 402 of the second reservoir portion 401 to control
the flow of liquid materials into and out of the second reservoir
portion 401. Finally, the apparatus 400 may further include a
conductive member 470 of the same type set forth above regarding
the conductive member 70 in apparatus 10, with all of the features
and functional capabilities of conductive member 70 being
applicable to conductive member 470. As illustrated in FIG. 12, the
conductive member 470 will preferably consist of an elongate wire
472 surrounded by a layer 473 of insulating material of the same
type as layer 73 in the first embodiment of the present invention.
The wire 472 likewise has the same characteristics as wire 72, with
the proximal end 474 of the wire 472 having a spherical member 486
thereon as illustrated. The conductive member 470 (e.g. wire 472)
is preferably secured to the underside 490 of the apparatus 400
shown in FIG. 12 adjacent the second stem portion 236 and the first
reservoir portion 220. Affixation may be accomplished using the
same materials set forth above regarding the conductive member 70.
The spherical member 486 is preferably positioned adjacent the
second end 210 of the first stem portion 204 as illustrated.
However, it should be noted that the position of the conductive
member 470 may be suitably varied and located at any position on
the apparatus 400. Also, the conductive member 470 may be extended
(lengthened) so that one or more spherical members (not shown) of
the same type as spherical member 486 are located at various
positions on the apparatus 400 (e.g. adjacent the third and/or
fourth stem portions 406, 422). The apparatus 400 shall not be
limited with respect to the length of the conductive member 470
(e.g. wire 472) or the number and placement of the spherical
members 486 operatively connected to the conductive member 470. The
conductive member 470 and components associated therewith are
designed for ECoG monitoring purposes as described herein.
It should be noted that, with respect to all of the embodiments
described herein involving apparatus 10, apparatus 200, and
apparatus 400, such devices shall not be limited regarding the
number and orientation of reservoir portions, valves, and/or stem
portions which are used therewith. Also, as indicated above with
respect to apparatus 200, the first stem portion 204 in apparatus
400 will preferably be in axial alignment with the second stem
portion 236 as illustrated. In this configuration, first stem
portion 204 is located on first side 250 of the first reservoir
portion 220, and the second stem portion 236 is located on second
side 252 of the first reservoir portion 220 (FIG. 7). As previously
discussed, first side 250 is directly opposite the second side 252
so that the first stem portion 204 is positioned at a 180.degree.
angle relative to the second stem portion 236.
The alternative treatment apparatus 400 illustrated in FIG. 12
provides all of the benefits set forth above regarding treatment
apparatus 200, but is further characterized by an improved
medicine-retaining capacity (due to the use of dual reservoir
portions 220, 401). Also, the use of additional stem portions (e.g.
third and fourth stem portions 406, 422) enables a greater
distribution of liquid medicine materials to a variety of inner ear
structures and related regions. In a preferred embodiment, the use
of third and fourth stem portions 406, 422 enables liquid medicines
to be delivered by capillary action to the endolymphatic
sac/endolymphatic duct, as well as to the subarachnoid space
adjacent the inner ear. Surgical insertion of the alternative
medicine treatment apparatus 400 may be accomplished in a number of
different ways. For example, the apparatus 400 may be implanted
into the endolymphatic sac and duct using standard techniques and
procedures as described in Pillsbury, H. C., III elt al. (ed.),
Operative challenges in Otolaryngology--Head and Neck Surgery,
Yearbook Medical Procedures, Chicago, 93-111: (1990)--(article
therein presented in Chapt. 7 entitled "Nondestructive Surgery for
Vertigo--Approach of I. Kaufman Arenberg, et al.) which is
incorporated herein by reference. Specifically, the first end 424
of the fourth stem portion 422 is placed through the endolymphatic
sac into the subarachnoid space (using a procedure described in
House, W. F., "Subarachnoid shunt for drainage of hydrops: a report
of 146 cases", Laryngoscope, 75:1547-1553 (1965)--incorporated
herein by reference). The second reservoir portion 401 remains at
the endolymphatic sac. The rest of the apparatus 400 is then
brought into the middle/inner ear via a posterior tympanotomy from
the mastoid cavity in the same manner traditionally used in
connection with cochlear implants as described in Pillsbury, H. C.,
III et al. (ed.), Operative challenges in Otolaryngology--Head and
Neck Surgery, Yearbook Medical Procedures, Chicago, 139-145:
(1990)--(article therein presented in Chapt. 10 entitled "Cochlear
Implants--Approach of William M. Luxford, et al.) which is also
incorporated herein by reference. In this regard, the first
reservoir portion 220 is positioned at the round window membrane in
the middle ear, with the second stem portion 236 and distal
portions of the elongate conductive member 470 being brought
through the tympanic membrane and external auditory canal in the
same manner set forth above regarding apparatus 200. It should be
noted that surgical insertion of the apparatus 400 may be
undertaken in a number of different ways, and the present invention
shall not be limited to the specific procedure outlined above.
Finally, the second reservoir portion 401, third stem portion 406
and fourth stem portion 422 are each preferably manufactured from
the same materials used to produce the remaining portions of the
apparatus 400 which is optimally of unitary construction.
In a still further alternative embodiment of the present invention,
means are provided wherein changes in inner ear fluid pressure,
temperature, and/or volume levels may be accomplished. As
previously indicated, a precise balance exists with respect to the
fluids of the inner ear (e.g. the endolymph and the perilymph).
These fluids are maintained within discrete tissue structures, with
the endolymph being retained within the endolymphatic system and
the perilymph being held within the perilymphatic system. If a
precise balance does not exist with respect to these fluid
materials, numerous problems may result as previously described
regarding endolymphatic hydrops, endolymphatic hypertension, and/or
perilymphatic hypertension. In the present invention, means are
provided wherein pressure changes relative to the foregoing fluids
may be accomplished in a substantially non-invasive manner. As
described below, these changes are undertaken by the direct
application of physical pressure to selected tissue structures,
with such physical pressure being transmitted directly to the
foregoing fluids. Alternatively, such changes in fluid pressure may
be accomplished by increasing or decreasing the temperature of the
fluids which cause corresponding changes in fluid volume and
pressure levels. For example, an increase in fluid temperature will
result in a thermal expansion of the fluid, thereby increasing its
volume and pressure levels in accordance with known physical
relationships involving fluid pressure, temperature, and
volume.
To specifically achieve the foregoing changes in fluid temperature,
pressure and volume levels, a modified treatment system 500
illustrated in FIG. 13 is provided. Basically, the system 500
includes two main components. The first component involves a
primary treatment apparatus 600 which is illustrated in FIG. 13.
From an external perspective, apparatus 600 is substantially
identical to apparatus 10 illustrated in FIG. 1, with all of the
information described above involving apparatus 10 being applicable
to apparatus 600 unless otherwise indicated. As shown in FIG. 13,
the apparatus 600 includes a body portion 612 which, as noted
above, is preferably of unitary (e.g. single-piece), molded
construction. In a preferred embodiment, the body portion 612 is
manufactured of a soft, resilient, elastic, and biologically inert
material with a preferred thickness of about 0.03-0.07 mm in order
to facilitate stretching of the apparatus 600 as described below.
Exemplary construction materials suitable for this purpose include
but are not limited to medical grade silicone rubber and other
equivalent compositions.
In addition, in certain instances, it may likewise be desirable to
manufacture all of part of the body portion 612 from medical grade
silicone rubber impregnated with BaSO.sub.4 or any other suitable
materials having similar characteristics which will render the body
portion 612 radiopaque when X-rays are applied thereto. This will
enable the treating physician to accurately determine the precise
location of the apparatus 600 within a patient after insertion.
With continued reference to FIG. 13, the body portion 612 further
includes a tubular primary stem portion 614. As shown in FIG. 13,
the primary stem portion 614 includes a continuous side wall 616
which is preferably annular (e.g. circular/ring-like) in
cross-section. The primary stem portion 614 further includes an
open first end 620, a second end 622, and a passageway 624
extending continuously through the primary stem portion 614 from
the open first end 620 to the second end 622. In a preferred
embodiment for use in connection with the human ear, the primary
stem portion 614 will have a diameter "D.sub.4 " and length
"L.sub.9 " comparable to the diameter "D.sub.1 " and length
"L.sub.1 " of the stem portion 14 in the apparatus 10 of FIG.
1.
Extending outwardly from the primary stem portion 614 as
illustrated in FIG. 13 is a secondary stem portion 625 having an
open first end 626, and a second end 627 which is operatively
connected to the primary stem portion 614 between the first end 620
and the second end 622. The secondary stem portion 625 has an
internal passageway 628 which extends continuously from the first
end 626 to the second end 627 and is in fluid communication with
the passageway 624 through the primary stem portion 614. The
function of the secondary stem portion 625 will be described
below.
With continued reference to. FIG. 13, the second end 622 of the
primary stem portion 614 is operatively and fixedly connected to an
enlarged reservoir portion 630 which is designed to retain a supply
of liquid, gel-type, or solid (e.g. crystalline or powdered)
medicines therein. As indicated above, it is preferred that the
body portion 612 of the primary treatment apparatus 600 be of
unitary (e.g. single-piece) molded construction. In this regard,
the primary stem portion 614 and the reservoir portion 630 are, in
a preferred embodiment, integrally formed together during
production of the apparatus 600.
The reservoir portion 630 may involve numerous different external
configurations such as those described above relative to reservoir
portion 30. Furthermore, as illustrated in FIG. 13, the reservoir
portion 630 includes an internal cavity 638 which is adapted to
receive liquid, gel-type, or solid medicines therein as described
in greater detail below. Attachment of the primary stem portion 614
to the reservoir portion 630 in the foregoing manner enables the
passageway 624 in the primary stem portion 614 to be in fluid
communication with the internal cavity 638 in the reservoir portion
630. While the volumetric capacity of the internal cavity 638 may
be suitably varied during manufacture of the apparatus 600, it is
preferred that the internal cavity 638 have a capacity of about
3.0-6.0 ml. Furthermore, as illustrated in FIG. 13, it is preferred
that the reservoir portion 630 have a length "L.sub.10 " and
thickness "T.sub.3 " approximately equal to the length "L.sub.2 "
and thickness "T.sub.1 " of the reservoir portion 30 in the
apparatus 10 described above. Likewise, the overall length
"L.sub.11 " of the body portion 612 will preferably be about equal
to the length "L.sub.3 " of the body portion 12 indicated
above.
The internal cavity 638 of the reservoir portion 630 is surrounded
by an exterior wall 642. So that medicine materials retained within
the internal cavity 638 of the reservoir portion 630 may be
effectively delivered to desired tissues within the middle/inner
ear, the wall 642 includes fluid transfer means therein generally
designated at reference number 643 in FIG. 13. The fluid transfer
means 643 may consist of a fenestrated zone 644 in the wall 642 of
the reservoir portion 630 as illustrated. The term "fenestrated" as
used herein involves a portion of the wall 642 having a plurality
of pores 646 (enlarged for the sake of clarity in FIG. 13)
therethrough. The pores 646 function in the same manner as the
pores 46 in the apparatus 10 described above. Likewise, all of the
other characteristics of the pores 646 are substantially identical
to the characteristics of pores 46 (e.g. size, quantity, etc.). As
far as the fluid transfer means 643 is concerned, other systems may
be used instead of the pores 646 for allowing liquid medicines to
pass out of the internal cavity 638 of the reservoir portion 630
during use of the apparatus 600. For example, the fluid transfer
means 643 may consist of a semi-permeable membrane (not shown) of
the type described above relative to membrane 54 or a micropore
filter of conventional design as indicated above relative to
apparatus 10.
Finally, as illustrated in FIG. 13, the apparatus 600 includes
electrical potential transmission means 688 fixedly secured to the
body portion 612 for receiving electrical potentials from
middle/inner ear tissues and transmitting them out of the ear for
the detection and analysis thereof. In a preferred embodiment, the
electrical potential transmission means 688 will consist of an
elongate conductive member 690 (e.g. in the form of a wire 692) of
exactly the same type as the conductive member 70 and wire 72. As
shown in FIG. 13, the wire 692 is covered with a layer 693 of
insulating material of the same type used in connection with the
layer 73 of insulation indicated above. Likewise, the conductive
member 690 (e.g. the wire 692) has a proximal end 694 and a distal
end 695. Accordingly, all of the information set forth above
relative to the structure, position, and function of the conductive
member 70 is equally applicable to the conductive member 690 which
likewise preferably includes a conductive spherical member 696
secured thereto (e.g. integrally formed as a part of the wire 692).
The spherical member 696 is substantially identical to the
spherical member 86 used in connection with the wire 72. As a
result, ECoG analyses may be undertaken in a rapid and efficient
manner.
So that the system 500 is capable of modifying the pressure,
temperature, and volumetric characteristics of inner ear fluid
materials (e.g. endolymph and/or perilymph), the system 500 further
includes a second component which is designed for insertion within
the primary treatment apparatus 600. With continued reference to
FIG. 13, the body portion 612 of the apparatus 600 is sized to
receive an inflatable insert member 700 having a body portion 712
which is preferably of unitary (e.g. single-piece), molded
construction. In a preferred embodiment, the body portion 712 is
manufactured of a soft, resilient, stretchable, and biologically
inert material. The stretchability of the body portion 712 is
especially important for the reasons described below. Exemplary
construction materials suitable for this purpose include but are
not limited to medical grade silicone or other equivalent materials
having a preferred thickness of about 0.03-0.07 mm.
In addition, in certain instances, it may again be desirable to
manufacture all of part of the body portion 712 from medical grade
silicone rubber impregnated with BaSO.sub.4 or any other suitable
materials having similar characteristics which will render the body
portion 712 radiopaque when X-rays are applied thereto. This will
enable the treating physician to accurately determine the precise
location of the apparatus 600 and insert member 700 within a
patient.
As shown in FIG. 13, the body portion 712 further includes an
elongate tubular portion 714. The tubular portion 714 includes a
continuous side wall 716 which is preferably annular (e.g. circular
or ring-like) in cross-section. The tubular portion 714 further
includes an open first end 720, a second end 722, and a passageway
724 extending continuously through the tubular portion 714 from the
first end 720 to the second end 722. In a preferred embodiment for
use in connection with the human ear, the tubular portion 714 will
have a diameter "D.sub.5 " which is uniform along the entire length
thereof from the first end 720 to the second end 722. This diameter
"D.sub.5 " will optimally be smaller than the diameter "D.sub.6 "
of the passageway 624 in the primary stem portion 614 of the
apparatus 600 so that the tubular portion 714 of the insert member
700 may be readily placed within the primary stem portion 614 of
the apparatus 600. Also, the foregoing relationship between
"D.sub.5 " and "D.sub.6 " ensures that fluid materials may be
readily delivered from external sources into the reservoir portion
630 of the apparatus 600 via the primary stem portion 614. In a
preferred embodiment for use in connection with the human ear, the
unexpanded diameter "D.sub.5 " of the tubular portion 714 will be
about 0.2-0.6 mm, and the diameter "D.sub.6 " of the passageway 624
in the apparatus 600 will be about 0.5-0.8 mm. Furthermore, the
length "L.sub.12 " (FIG. 13) of the tubular portion 714 will
preferably be longer than the length "L.sub.9 " of the primary stem
portion 614 of the apparatus 600. Optimally, "L.sub.12 " will be
about 10.0-30.0 mm.
With continued reference to FIG. 13, the second end 722 of the
tubular portion 714 is operatively and fixedly connected to a
bulb-like fluid receiving portion 730. As indicated above, it is
preferred that the body portion 712 of the insert member 700 be of
unitary (e.g. single-piece) molded construction. In this regard,
the tubular portion 714 and the fluid receiving portion 730 are, in
a preferred embodiment, integrally formed together during
production.
The fluid receiving portion 730 may involve numerous different
external configurations. With reference to FIG. 13, the fluid
receiving portion 730 is configured in an oval (e.g. ovoid) shape
substantially identical in configuration with the configuration of
the internal cavity 638 in the apparatus 600 as illustrated. While
the present invention shall not be limited with respect to the
shape of the fluid receiving portion 730, it is preferred that the
fluid receiving portion 730 have a shape which does, in fact,
correspond with the shape of the internal cavity 638 in the
apparatus 600. The fluid receiving portion 730 further includes an
internal cavity 738 surrounded by an exterior wall 739. The cavity
738 is adapted to receive a supply of pressurized liquid or gas
therein. For the purposes of this invention, the term "fluid" shall
be used to signify either liquids or gases supplied to the internal
cavity 738 of the fluid receiving portion 730. In addition, as
shown in FIG. 13, attachment of the tubular portion 714 to the
fluid receiving portion 730 in the foregoing manner enables the
passageway 724 in the tubular portion 714 to be in fluid
communication with the internal cavity 738 in the fluid receiving
portion 730. While the volumetric capacity of the internal cavity
738 may be suitably varied during manufacture of the insert member
700, it is preferred that the internal cavity 738 have an ambient,
unexpanded capacity of about 0.50-1.0 ml. However, in view of the
stretchable nature of the fluid receiving portion 730 as described
above, this numerical range may increase substantially, depending
on the amount of fluid materials being delivered thereto as well as
the pressure of such materials. Furthermore, as illustrated in FIG.
13, it is preferred that the fluid receiving portion 730 have a
length "L.sub.13 " of about 2.0-8.0 mm and a thickness "T.sub.4 "
of about 0.5-7.0 mm which are less than the length "L.sub.10 " and
thickness "T.sub.3 " of the reservoir portion 630 of the apparatus
600. In fact, the dimensions of the fluid receiving portion 730 are
smaller than those of the internal cavity 638 of the reservoir
portion 630 in order to enable the portion 730 to readily fit
within the internal cavity 638 as shown in FIG. 14 (which involves
an enlarged cross-sectional view of the apparatus 600 having the
insert member 700 mounted therein.) As a result, fluid materials
747 (FIG. 14) will be able to reside within the internal cavity
638. Likewise, as noted above, the tubular portion 714 is smaller
than the passageway 624 in the primary stem portion 614 so that the
foregoing fluid materials may be supplied to the internal cavity
638 of the primary treatment apparatus 600 via passageways 624, 628
(FIGS. 14). In addition, it is important to note that the total
length "L.sub.14 " of the insert member 700 as shown in FIG. 13 is
about 13.0-38.0 mm.
It should also be noted that the insert member 700 may be
positioned within the body portion 612 of the apparatus 600 in a
number of different ways. For example, during the manufacturing
process, the body portion 612 of the apparatus 600 may be molded
directly over and around the previously formed insert member 700.
Alternatively, in view of the highly stretchable nature of the
apparatus 600, the insert member 700 may be suitably urged into the
apparatus 600 using any blunt, elongate instrument. As the insert
member 700 is being urged into the apparatus 600, the body portion
612 will stretch, thereby facilitating placement of the insert
member 700 in position within the body portion 612.
As noted above, FIG. 14 involves a cross-sectional view of the
system 500 wherein the insert member 700 is positioned within the
apparatus 600. In FIG. 14, the elongate conductive member 690 has
been omitted for the sake of clarity. Because the insert member 700
in a non-inflated state has smaller overall dimensions than the
interior regions of the apparatus 600 (e.g. the tubular portion 714
is smaller than the passageway 624 and the fluid receiving portion
730 is smaller than the internal cavity 638), an open zone 748 will
exist around the insert member 700 as shown. The function of this
zone 748 will be described below.
The apparatus 600 (with the insert member 700 therein) is then
surgically inserted within a patient so that the reservoir portion
630 is located in the middle ear and in direct physical contact
with a selected middle-inner ear interface tissue structure (e.g.
the round window membrane). Likewise, the apparatus 600 is inserted
so that at least part of the primary stem portion 614 (e.g. the
open first end 620 thereof) is positioned within the external
auditory canal at a position remotely spaced from the middle ear
(see FIG. 15 described below). Surgical insertion and placement in
this manner is again normally accomplished via an incision in the
tympanic membrane which is undertaken using standard tympanotomy
procedures as described above relative to the insertion of
apparatus 10. Alternatively, insertion and placement of the
apparatus 600 may be accomplished using a standard tympanomeatal
flap procedure which likewise provides access to the middle ear and
structures thereof. In addition, the apparatus 600 is preferably
oriented so that at least a section of the primary stem portion 614
of the apparatus 600 extends through the incised tympanic membrane
(or under the foregoing tympanomeatal flap), and resides within the
external auditory canal of the patient.
FIG. 15 is a schematic, partial cross-sectional view of the ear 749
of a human subject illustrating the system 500 of FIGS. 13-14
inserted therein. As shown, the primary treatment apparatus 600
with the insert member 700 therein is positioned so that the
reservoir portion 630 of the apparatus 600 is entirely within the
middle ear, generally designated in FIG. 15 at reference number
750. The inner ear is generally designated in FIG. 15 at reference
number 751, and further includes the cochlea 752, the endolymphatic
sac 753, and the endolymphatic duct 754. The round window membrane
is designated at reference number 755, and again constitutes an
interface tissue structure between the middle ear 750 and the inner
ear 751.
In FIG. 15, the reservoir portion 630 of the apparatus 600 is
specifically positioned so that the fluid transfer means 643 is in
direct physical contact with the round window membrane 755.
Likewise, in order to transmit/receive electric potentials from the
inner ear, the spherical member 696 on the proximal end 694 of the
elongate conductive member 690 (e.g. wire 692) is positioned
against and in direct contact with the round window membrane 755 in
the middle ear 750. Prior to insertion of the apparatus 600 (and
insert member 700) within the ear 749, the open first end 720 of
the tubular portion 714 associated with the insert member 700 is
operatively connected to the first end 758 of a tubular conduit 760
made of surgical grade plastic preferably using an adhesive
composition known in the art (e.g. silastic cement) or by
frictional engagement therewith. Connection of these components in
this manner is facilitated by the fact that the tubular portion 714
of the insert member 700 is longer than the primary stem portion
614 of the apparatus 600. Therefore, the open first end 720 of the
tubular portion 714 extends outwardly beyond the open first end 620
of the primary stem portion 614 as illustrated in FIG. 15. The
conduit 760 further includes a second end 762 which is operatively
connected to a fluid supply means 763 in the form of a source or
supply 764 of fluid (e.g. water, air, or other liquids and gases).
The supply 764 will include pump means 769 in the form of a
conventional pressure pump unit 770 associated therewith, as well
as temperature control means 771 in the form of a temperature
control unit 772. In a preferred embodiment, if the supply 764 is
designed to deliver water or other liquid materials, an exemplary
supply 764 (and the above-described components associated
therewith) will consist of a closed loop irrigation system of the
type disclosed in Brookler, K. H., "Closed Loop Water Irrigator
System", Otolaryngol. Head Neck Surg., 87:364-365 (May-June 1979)
which is incorporated herein by reference. This system is designed
to deliver fluid to a balloon-type structure which is maintained at
a temperature of about 28.degree.-46.degree. C. It is further
discussed in U.S. Pat. No. 4,244,377 and is commercially available
from Grams, Inc. of Costa Mesa, Calif. (USA). However, the present
invention shall not be exclusively limited to this type of system.
Any other type of fluid delivery and/or pressure/volume/temperature
regulating system which is known in the art for the purposes set
forth herein may also be employed.
Alternatively, if it is desired that the supply 764 of fluid
deliver air or other gaseous materials, a system suitable for this
purpose which includes the foregoing components is described in
Densert, B., "Effects of Overpressure on Hearing Function in
Meniere's Disease", Acta Otolaryngol. 103:32-42 (1987) and in U.S.
Pat. No. 4,971,076. However, the present invention shall not be
limited exclusively to the systems described in the foregoing
references.
To operate the primary treatment apparatus 600 with the insert
member 700 therein so that changes in the inner ear fluid,
temperature, volume and/or pressure levels may be achieved, the
supply 764 of fluid and the pump unit 770 are activated so that the
selected fluid is delivered through the conduit 760 into the
tubular portion 714 of the insert member 700, and into the fluid
receiving portion 730 thereof. The fluid (e.g. air or water) is
supplied at a pressure sufficient to cause expansion of the fluid
receiving portion 730 which is able to occur due to the stretchable
materials used to produce the insert member 700 as previously
indicated. As the fluid receiving portion 730 expands, it pushes
against the side wall 642 of the reservoir portion 630 in the
apparatus 600 and ultimately causes the reservoir portion 630 to
correspondingly expand in an outward direction. With respect to the
applied fluid pressure, such pressure will need to be determined
experimentally for each different patient based on the degree of
fluid imbalance within the particular patient's inner ear fluid
chambers. However, an exemplary liquid pressure range regarding the
delivery of liquids from the supply 764 to the fluid receiving
portion 730 of the insert member 700 will be about 0.2-200.0 mm
H.sub.2 O which should cause the fluid receiving portion 730 and
reservoir portion 630 to sufficiently expand as described above. An
exemplary gas pressure range with respect to the delivery of gases
from the supply 764 to the fluid receiving portion 730 of the
insert member 700 will be about 0.1-300.0 mm H.sub.2 O which should
again cause the fluid receiving portion 730 and reservoir portion
630 to sufficiently expand. It should also be noted that the
delivery of pressurized fluid from the supply 764 to the insert
member 700 may be continuous (e.g. so that the fluid receiving
portion 730 will remain in an expanded state for a selected period
of time), or may be done in discrete rhythmic or arrhythmic pulses.
In addition, if liquid medicine materials or other therapeutic
agents are present within the internal cavity 638 of the primary
treatment apparatus 600, the insert member 700 can be used to
selectively force the liquid medicine materials or agents outwardly
in an accelerated manner through the fluid transfer means 643 in
the apparatus 600 as desired. This may be accomplished through the
delivery of a selected fluid from the supply 764 to the insert
member 700 in pulses at desired intervals.
Because the reservoir portion 630 of the apparatus 600 will
ultimately be positioned directly adjacent to and against a
selected middle-inner ear interface tissue structure (e.g. the
round window membrane 755 as shown in FIG. 15), expansion of the
reservoir portion 630 initiated by the insert member 700 will exert
pressure on the selected interface tissue structure, with such
pressure being transmitted to fluid materials within the inner ear
751. As a result, this procedure will correct fluid pressure
imbalances within the inner ear on a temporary or permanent basis
(depending on the extent of fluid pressure imbalance). In addition,
the temperature control unit 772 associated with the source 764 of
fluid may be used to heat or cool the liquids or gases prior to
delivery thereof to the insert member 700. The delivery of heated
or cooled fluids to the fluid receiving portion 730 will cause a
corresponding increase or decrease in the temperature of the fluid
receiving portion 730 which may then be conductively transmitted
from the fluid receiving portion 730 to the reservoir portion 630
and into the inner ear 751 via the selected middle-inner ear
interface tissue structure (e.g. the round window membrane 755).
This situation will occur since the reservoir portion 630 is in
direct physical contact with the round window membrane 755 as shown
in FIG. 15. If heated fluids are delivered to the insert member
700, the inner ear fluids/fluid chambers will likewise experience
an increase in temperature and therefore expand, causing the volume
and pressure characteristics thereof to increase. The opposite
result will be achieved if cooled fluid materials are delivered.
Regarding the temperatures of the liquids or gases to be delivered
to the insert member 700, the selected temperature levels will
vary, depending on (1) the condition of the patient and extent of
inner ear fluid imbalances; (2) the type of fluid being delivered
to the insert member 700; and (3) the degree of pressure exerted by
the expanded insert member 700 and reservoir portion 630 against
the selected middle-inner ear interface tissue structure (e.g. the
round window membrane 755). Liquid temperatures within a broad
range of about 30.degree.-44.degree. C. are preferred, while gas
temperatures within a broad range of about 20.degree.-50.degree. C.
may be employed. However, such temperatures are provided for
example purposes and the present invention shall not be limited to
any particular temperature level as long as the selected
temperature is not permanently and physically injurious to ear
tissues (unless such effects are the goal of the particular
treatment program being administered).
It should be noted that when the insert member 700 is in a deflated
state, fluid materials may still be readily added to the reservoir
portion 630 of the primary treatment apparatus 600 in the same
general manner set forth above regarding the apparatus 10. Fluid
addition is specifically accomplished through the open first end
626 of the secondary stem portion 625. The fluid is then able to
pass through the passageway 624 in the primary stem portion 614 by
virtue of the open zone 748 which exists between the deflated
insert member 700 and the apparatus 600 as described above.
Finally, it should likewise be noted that the primary treatment
apparatus 600 may be configured so that it does not include fluid
transfer means (e.g. pores 646) therein. The system 500 using
apparatus 600 without the fluid transfer means would nonetheless
function in the same manner as described above, except that the
system 500 would not be used to deliver fluid materials to the
middle/inner ear.
The present invention represents a substantial advance in the art
of middle and inner ear treatment. Use of the invention enables a
wide variety of therapeutic procedures to be readily accomplished
using aminimal number of physical components and minimally invasive
surgical procedures. Specifically, the various embodiments of the
invention set forth herein enable (1) the delivery of therapeutic
agents to internal ear (e.g. inner ear) structures; (2) the
withdrawal of fluid materials from the inner ear; (3) the
inducement of temperature, pressure and volumetric changes in the
fluids/fluid chambers of the inner ear; and (4) the
electrophysiological monitoring of internal (e.g. inner) ear
structures. Thus, the present invention and the structures/methods
associated therewith represent a significant development with
respect to the treatment of middle and inner ear problems.
Having herein described preferred embodiments of the present
invention, it is anticipated that suitable modifications may be
made thereto by individuals skilled in the art which nonetheless
remain within the scope of the invention. For example, the present
invention shall not be limited with respect to the construction
materials being employed, the size thereof, the therapeutic agents
being delivered, and the physiological environment in which the
invention is used. The present invention shall therefore only be
construed in accordance with the following claims:
* * * * *